\u672c\u7ae0\u6db5\u76d6<\/h2>\n\n- Mapping URLs to endpoint handlers
\n\u5c06 URL \u6620\u5c04\u5230\u7aef\u70b9\u5904\u7406\u7a0b\u5e8f<\/li>\n - Using constraints and default values to match URLs
\n\u4f7f\u7528\u7ea6\u675f\u548c\u9ed8\u8ba4\u503c\u6765\u5339\u914d URL<\/li>\n - Generating URLs from route parameters
\n\u4ece\u8def\u7531\u53c2\u6570\u751f\u6210 URL<\/li>\n<\/ul>\nIn chapter 5 you learned how to define minimal APIs, how to return responses, and how to work with filters and route groups. One crucial aspect of minimal APIs that we touched on only lightly is how ASP.NET Core selects a specific endpoint from all the handlers defined, based on the incoming request URL. This process, called routing, is the focus of this chapter.<\/p>\n
\u5728\u7b2c 5 \u7ae0\u4e2d\uff0c\u60a8\u5b66\u4e60\u4e86\u5982\u4f55\u5b9a\u4e49\u6700\u5c0f API\u3001\u5982\u4f55\u8fd4\u56de\u54cd\u5e94\u4ee5\u53ca\u5982\u4f55\u4f7f\u7528\u7b5b\u9009\u6761\u4ef6\u548c\u8def\u7531\u7ec4\u3002\u6211\u4eec\u4ec5\u7565\u5fae\u6d89\u53ca\u7684\u6700\u5c0f API \u7684\u4e00\u4e2a\u5173\u952e\u65b9\u9762\u662f ASP.NET Core \u5982\u4f55\u6839\u636e\u4f20\u5165\u8bf7\u6c42 URL \u4ece\u5b9a\u4e49\u7684\u6240\u6709\u5904\u7406\u7a0b\u5e8f\u4e2d\u9009\u62e9\u7279\u5b9a\u7aef\u70b9\u3002\u6b64\u8fc7\u7a0b\u79f0\u4e3a routing\uff0c\u662f\u672c\u7ae0\u7684\u91cd\u70b9\u3002<\/p>\n
This chapter begins by identifying the need for routing and why it\u2019s useful. You\u2019ll learn about the endpoint routing system introduced in ASP.NET Core 3.0 and why it was introduced, and explore the flexibility routing can bring to the URLs you expose.<\/p>\n
\u672c\u7ae0\u9996\u5148\u786e\u5b9a routing \u7684\u9700\u6c42\u4ee5\u53ca\u5b83\u4e3a\u4ec0\u4e48\u6709\u7528\u3002\u60a8\u5c06\u4e86\u89e3 ASP.NET Core 3.0 \u4e2d\u5f15\u5165\u7684\u7aef\u70b9\u8def\u7531\u7cfb\u7edf\u53ca\u5176\u5f15\u5165\u539f\u56e0\uff0c\u5e76\u63a2\u7d22\u8def\u7531\u53ef\u4ee5\u4e3a\u60a8\u516c\u5f00\u7684 URL \u5e26\u6765\u7684\u7075\u6d3b\u6027\u3002<\/p>\n
The bulk of this chapter focuses on the route template syntax and how it can be used with minimal APIs. You\u2019ll learn about features such as optional parameters, default parameters, and constraints, as well as how to extract values from the URL automatically. Although we\u2019re focusing on minimal APIs in this chapter, the same routing system is used with Razor Pages and Model-View-Controller (MVC), as you\u2019ll see in chapter 14.<\/p>\n
\u672c\u7ae0\u7684\u5927\u90e8\u5206\u5185\u5bb9\u91cd\u70b9\u4ecb\u7ecd\u8def\u7531\u6a21\u677f\u8bed\u6cd5\u4ee5\u53ca\u5982\u4f55\u5c06\u5176\u4e0e\u6700\u5c11\u7684 API \u4e00\u8d77\u4f7f\u7528\u3002\u60a8\u5c06\u4e86\u89e3\u53ef\u9009\u53c2\u6570\u3001\u9ed8\u8ba4\u53c2\u6570\u548c\u7ea6\u675f\u7b49\u529f\u80fd\uff0c\u4ee5\u53ca\u5982\u4f55\u81ea\u52a8\u4ece URL \u4e2d\u63d0\u53d6\u503c\u3002\u5c3d\u7ba1\u6211\u4eec\u5728\u672c\u7ae0\u4e2d\u91cd\u70b9\u4ecb\u7ecd\u4e86\u6700\u5c11\u7684 API\uff0c\u4f46 Razor Pages \u548c\u6a21\u578b\u89c6\u56fe\u63a7\u5236\u5668 \uff08MVC\uff09 \u4f7f\u7528\u76f8\u540c\u7684\u8def\u7531\u7cfb\u7edf\uff0c\u5982\u7b2c 14 \u7ae0\u6240\u793a\u3002<\/p>\n
In section 6.4 I describe how to use the routing system to generate URLs, which you can use to create links and redirect requests for your application. One benefit of using a routing system is that it decouples your handlers from the underlying URLs they\u2019re associated with. You can use URL generation to avoid littering your code with hardcoded URLs like \/product\/view\/3. Instead, you can generate the URLs at runtime, based on the routing system. This approach makes changing the URL for a given endpoint easier: instead of your having to hunt down every place where you used the endpoint\u2019s URL, the URLs are updated for you automatically, with no other changes required.<\/p>\n
\u5728 6.4 \u8282\u4e2d\uff0c\u6211\u5c06\u4ecb\u7ecd\u5982\u4f55\u4f7f\u7528\u8def\u7531\u7cfb\u7edf\u751f\u6210 URL\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u8fd9\u4e9b URL \u4e3a\u60a8\u7684\u5e94\u7528\u7a0b\u5e8f\u521b\u5efa\u94fe\u63a5\u548c\u91cd\u5b9a\u5411\u8bf7\u6c42\u3002\u4f7f\u7528\u8def\u7531\u7cfb\u7edf\u7684\u4e00\u4e2a\u597d\u5904\u662f\uff0c\u5b83\u5c06\u5904\u7406\u7a0b\u5e8f\u4e0e\u5b83\u4eec\u5173\u8054\u7684\u5e95\u5c42 URL \u5206\u79bb\u3002\u60a8\u53ef\u4ee5\u4f7f\u7528 URL \u751f\u6210\u6765\u907f\u514d\u5c06\u4ee3\u7801\u4e0e\u786c\u7f16\u7801\u7684 URL \uff08\u5982 \/product\/view\/3\uff09\u6df7\u5728\u4e00\u8d77\u3002\u76f8\u53cd\uff0c\u60a8\u53ef\u4ee5\u5728\u8fd0\u884c\u65f6\u6839\u636e\u8def\u7531\u7cfb\u7edf\u751f\u6210 URL\u3002\u8fd9\u79cd\u65b9\u6cd5\u4f7f\u66f4\u6539\u7ed9\u5b9a\u7ec8\u7aef\u8282\u70b9\u7684 URL \u53d8\u5f97\u66f4\u52a0\u5bb9\u6613\uff1a\u60a8\u4e0d\u5fc5\u5bfb\u627e\u4f7f\u7528\u7ec8\u7aef\u8282\u70b9 URL \u7684\u6bcf\u4e2a\u4f4d\u7f6e\uff0cURL \u4f1a\u81ea\u52a8\u4e3a\u60a8\u66f4\u65b0\uff0c\u65e0\u9700\u8fdb\u884c\u5176\u4ed6\u66f4\u6539\u3002<\/p>\n
By the end of this chapter, you should have a much clearer understanding of how an ASP.NET Core application works. You can think of routing as being the glue that ties the middleware pipeline to endpoints. With middleware, endpoints, and routing under your belt, you\u2019ll be writing web apps in no time!<\/p>\n
\u5728\u672c\u7ae0\u7ed3\u675f\u65f6\uff0c\u60a8\u5e94\u8be5\u5bf9 ASP.NET Core \u5e94\u7528\u7a0b\u5e8f\u7684\u5de5\u4f5c\u539f\u7406\u6709\u4e86\u66f4\u6e05\u6670\u7684\u4e86\u89e3\u3002\u60a8\u53ef\u4ee5\u5c06\u8def\u7531\u89c6\u4e3a\u5c06\u4e2d\u95f4\u4ef6\u7ba1\u9053\u4e0e\u7ec8\u7aef\u8282\u70b9\u8054\u7cfb\u8d77\u6765\u7684\u7c98\u5408\u5242\u3002\u6709\u4e86\u4e2d\u95f4\u4ef6\u3001\u7ec8\u7aef\u8282\u70b9\u548c\u8def\u7531\uff0c\u60a8\u5c06\u7acb\u5373\u7f16\u5199 Web \u5e94\u7528\u7a0b\u5e8f\uff01<\/p>\n
6.1 What is routing?<\/h2>\n6.1 \u4ec0\u4e48\u662f\u8def\u7531\uff1f<\/h2>\n
Routing is the process of mapping an incoming request to a method that will handle it. You can use routing to control the URLs you expose in your application. You can also use routing to enable powerful features such as mapping multiple URLs to the same handler and automatically extracting data from a request\u2019s URL.<\/p>\n
\u8def\u7531\u662f\u5c06\u4f20\u5165\u8bf7\u6c42\u6620\u5c04\u5230\u5c06\u5904\u7406\u8be5\u8bf7\u6c42\u7684\u65b9\u6cd5\u7684\u8fc7\u7a0b\u3002\u60a8\u53ef\u4ee5\u4f7f\u7528\u8def\u7531\u6765\u63a7\u5236\u5728\u5e94\u7528\u7a0b\u5e8f\u4e2d\u516c\u5f00\u7684 URL\u3002\u60a8\u8fd8\u53ef\u4ee5\u4f7f\u7528\u8def\u7531\u6765\u542f\u7528\u5f3a\u5927\u7684\u529f\u80fd\uff0c\u4f8b\u5982\u6620\u5c04\u591a\u4e2a URL \u6307\u5411\u540c\u4e00\u5904\u7406\u7a0b\u5e8f\uff0c\u5e76\u81ea\u52a8\u4ece\u8bf7\u6c42\u7684 URL \u4e2d\u63d0\u53d6\u6570\u636e\u3002<\/p>\n
In chapter 4 you saw that an ASP.NET Core application contains a middleware pipeline, which defines the behavior of your application. Middleware is well suited to handling both cross-cutting concerns, such as logging and error handling, and narrowly focused requests, such as requests for images and CSS files.<\/p>\n
\u5728\u7b2c 4 \u7ae0\u4e2d\uff0c\u60a8\u770b\u5230 ASP.NET Core \u5e94\u7528\u7a0b\u5e8f\u5305\u542b\u4e00\u4e2a\u4e2d\u95f4\u4ef6\u7ba1\u9053\uff0c\u5b83\u5b9a\u4e49\u4e86\u5e94\u7528\u7a0b\u5e8f\u7684\u884c\u4e3a\u3002\u4e2d\u95f4\u4ef6\u975e\u5e38\u9002\u5408\u5904\u7406\u6a2a\u5207\u5173\u6ce8\u70b9\uff08\u5982\u65e5\u5fd7\u8bb0\u5f55\u548c\u9519\u8bef\u5904\u7406\uff09\u548c\u8303\u56f4\u72ed\u7a84\u7684\u8bf7\u6c42\uff08\u5982\u56fe\u50cf\u548c CSS \u6587\u4ef6\u8bf7\u6c42\uff09\u3002<\/p>\n
To handle more complex application logic, you\u2019ll typically use the EndpointMiddleware at the end of your middleware pipeline. This middleware can handle an appropriate request by invoking a method known as a handler and using the result to generate a response. Previous chapters described using minimal API endpoint handlers, but there are other types of handlers, such as MVC Action methods and Razor Pages, as you\u2019ll learn in part 2 of this book.<\/p>\n
\u4e3a\u4e86\u5904\u7406\u66f4\u590d\u6742\u7684\u5e94\u7528\u7a0b\u5e8f\u903b\u8f91\uff0c\u60a8\u901a\u5e38\u4f1a\u5728\u4e2d\u95f4\u4ef6\u7ba1\u9053\u7684\u672b\u5c3e\u4f7f\u7528 EndpointMiddleware\u3002\u6b64\u4e2d\u95f4\u4ef6\u53ef\u4ee5\u901a\u8fc7\u8c03\u7528\u79f0\u4e3a\u5904\u7406\u7a0b\u5e8f\u7684\u65b9\u6cd5\u5e76\u4f7f\u7528\u7ed3\u679c\u751f\u6210\u54cd\u5e94\u6765\u5904\u7406\u9002\u5f53\u7684\u8bf7\u6c42\u3002\u524d\u9762\u7684\u7ae0\u8282\u4ecb\u7ecd\u4e86\u4f7f\u7528\u6700\u5c11\u7684 API \u7aef\u70b9\u5904\u7406\u7a0b\u5e8f\uff0c\u4f46\u8fd8\u6709\u5176\u4ed6\u7c7b\u578b\u7684\u5904\u7406\u7a0b\u5e8f\uff0c\u4f8b\u5982 MVC\u4f5c\u65b9\u6cd5\u548c Razor Pages\uff0c\u60a8\u5c06\u5728\u672c\u4e66\u7684\u7b2c 2 \u90e8\u5206\u4e2d\u5b66\u4e60\u3002<\/p>\n
One aspect that I\u2019ve glossed over so far is how the EndpointMiddleware selects which handler executes when you receive a request. What makes a request appropriate for a given handler? The process of mapping a request to a handler is routing.<\/p>\n
\u5230\u76ee\u524d\u4e3a\u6b62\uff0c\u6211\u6240\u8ba8\u8bba\u7684\u4e00\u4e2a\u65b9\u9762\u662f EndpointMiddleware \u5982\u4f55\u9009\u62e9\u5728\u60a8\u6536\u5230\u8bf7\u6c42\u65f6\u6267\u884c\u54ea\u4e2a\u5904\u7406\u7a0b\u5e8f\u3002\u4ec0\u4e48\u4f7f\u8bf7\u6c42\u9002\u5408\u7ed9\u5b9a\u7684\u5904\u7406\u7a0b\u5e8f\uff1f\u5c06\u8bf7\u6c42\u6620\u5c04\u5230\u5904\u7406\u7a0b\u5e8f\u7684\u8fc7\u7a0b\u662f\u8def\u7531\u3002<\/p>\n
Definition<\/strong> Routing in ASP.NET Core is the process of selecting a specific handler for an incoming HTTP request. In minimal APIs, the handler is the endpoint handler associated with a route. In Razor Pages, the handler is a page handler method defined in a Razor Page. In MVC, the handler is an action method in a controller.
\n\u5b9a\u4e49<\/strong> ASP.NET Core \u4e2d\u7684\u8def\u7531\u662f\u4e3a\u4f20\u5165\u7684 HTTP \u8bf7\u6c42\u9009\u62e9\u7279\u5b9a\u5904\u7406\u7a0b\u5e8f\u7684\u8fc7\u7a0b\u3002\u5728\u6700\u5c0f API \u4e2d\uff0c\u5904\u7406\u7a0b\u5e8f\u662f\u4e0e\u8def\u7531\u5173\u8054\u7684\u7aef\u70b9\u5904\u7406\u7a0b\u5e8f\u3002\u5728 Razor Pages \u4e2d\uff0c\u5904\u7406\u7a0b\u5e8f\u662f\u5728 Razor Page \u4e2d\u5b9a\u4e49\u7684\u9875\u9762\u5904\u7406\u7a0b\u5e8f\u65b9\u6cd5\u3002\u5728 MVC \u4e2d\uff0c\u5904\u7406\u7a0b\u5e8f\u662f\u63a7\u5236\u5668\u4e2d\u7684\u4f5c\u65b9\u6cd5\u3002<\/p>\nIn chapters 3 to 5, you saw several simple applications built with minimal APIs. In chapter 5, you learned the basics of routing for minimal APIs, but it\u2019s worth exploring why routing is useful as well as how to use it. Even a simple URL path such as \/person uses routing to determine which handler should be executed, as shown in figure 6.1.<\/p>\n
\u5728\u7b2c 3 \u7ae0\u5230\u7b2c 5 \u7ae0\u4e2d\uff0c\u60a8\u770b\u5230\u4e86\u51e0\u4e2a\u4f7f\u7528\u6700\u5c11 API \u6784\u5efa\u7684\u7b80\u5355\u5e94\u7528\u7a0b\u5e8f\u3002\u5728\u7b2c 5 \u7ae0\u4e2d\uff0c\u60a8\u5b66\u4e60\u4e86\u6700\u5c0f API \u7684\u8def\u7531\u57fa\u7840\u77e5\u8bc6\uff0c\u4f46\u503c\u5f97\u63a2\u7d22\u4e3a\u4ec0\u4e48\u8def\u7531\u5f88\u6709\u7528\u4ee5\u53ca\u5982\u4f55\u4f7f\u7528\u5b83\u3002\u5373\u4f7f\u662f\u7b80\u5355\u7684 URL \u8def\u5f84\uff0c\u5982 \/person\uff0c\u4e5f\u4f7f\u7528\u8def\u7531\u6765\u786e\u5b9a\u5e94\u8be5\u6267\u884c\u54ea\u4e2a\u5904\u7406\u7a0b\u5e8f\uff0c\u5982\u56fe 6.1 \u6240\u793a\u3002<\/p>\n
![\"\"](\"\/images\/aspnetcoreinaction\/0601.png\")
<\/p>\n
Figure 6.1 The router compares the request URL with a list of configured route templates to determine which handler to execute.
\n\u56fe 6.1 \u8def\u7531\u5668\u5c06\u8bf7\u6c42 URL \u4e0e\u5df2\u914d\u7f6e\u7684\u8def\u7531\u6a21\u677f\u5217\u8868\u8fdb\u884c\u6bd4\u8f83\uff0c\u4ee5\u786e\u5b9a\u8981\u6267\u884c\u54ea\u4e2a\u5904\u7406\u7a0b\u5e8f\u3002<\/p>\n
On the face of it, that seems pretty simple. You may wonder why I need a whole chapter to explain that obvious mapping. The simplicity of the mapping in this case belies how powerful routing can be. If this approach, using a direct comparison with static strings, were the only one available, you\u2019d be severely limited in the applications you could feasibly build.<\/p>\n
\u4ece\u8868\u9762\u4e0a\u770b\uff0c\u8fd9\u4f3c\u4e4e\u5f88\u7b80\u5355\u3002\u4f60\u53ef\u80fd\u4f1a\u60f3\u4e3a\u4ec0\u4e48\u6211\u9700\u8981\u4e00\u6574\u7ae0\u6765\u89e3\u91ca\u8fd9\u4e2a\u660e\u663e\u7684\u6620\u5c04\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u6620\u5c04\u7684\u7b80\u5355\u6027\u63a9\u76d6\u4e86\u8def\u7531\u7684\u5f3a\u5927\u529f\u80fd\u3002\u5982\u679c\u8fd9\u79cd\u65b9\u6cd5\uff08\u4f7f\u7528\u4e0e\u9759\u6001\u5b57\u7b26\u4e32\u7684\u76f4\u63a5\u6bd4\u8f83\uff09\u662f\u552f\u4e00\u53ef\u7528\u7684\u65b9\u6cd5\uff0c\u90a3\u4e48\u60a8\u53ef\u4ee5\u6784\u5efa\u7684\u5e94\u7528\u7a0b\u5e8f\u5c06\u53d7\u5230\u4e25\u91cd\u9650\u5236\u3002<\/p>\n
Consider an e-commerce application that sells multiple products. Each product needs to have its own URL, so if you were using a purely static routing system, you\u2019d have only two options:<\/p>\n
\u8003\u8651\u4e00\u4e2a\u9500\u552e\u591a\u79cd\u4ea7\u54c1\u7684\u7535\u5b50\u5546\u52a1\u5e94\u7528\u7a0b\u5e8f\u3002\u6bcf\u4e2a\u4ea7\u54c1\u90fd\u9700\u8981\u6709\u81ea\u5df1\u7684 URL\uff0c\u56e0\u6b64\u5982\u679c\u60a8\u4f7f\u7528\u7684\u662f\u7eaf\u9759\u6001\u8def\u7531\u7cfb\u7edf\uff0c\u5219\u53ea\u6709\u4e24\u4e2a\u9009\u9879\uff1a<\/p>\n
\n- \n
Use a different handler for every product in your product range. That approach would be unfeasible for almost any realistically sized product range.
\n\u4e3a\u60a8\u7684\u4ea7\u54c1\u7cfb\u5217\u4e2d\u7684\u6bcf\u4e2a\u4ea7\u54c1\u4f7f\u7528\u4e0d\u540c\u7684\u5904\u7406\u7a0b\u5e8f\u3002\u8fd9\u79cd\u65b9\u6cd5\u5bf9\u4e8e\u51e0\u4e4e\u4efb\u4f55\u5b9e\u9645\u89c4\u6a21\u7684\u4ea7\u54c1\u7cfb\u5217\u90fd\u662f\u4e0d\u53ef\u884c\u7684\u3002<\/p>\n<\/li>\n
- \n
Use a single handler, and use the query string to differentiate among products. This approach is much more practical, but you\u2019d end up with somewhat-ugly URLs, such as "\/product?name=big-widget" or "\/product?id=12".
\n\u4f7f\u7528\u5355\u4e2a\u5904\u7406\u7a0b\u5e8f\uff0c\u5e76\u4f7f\u7528\u67e5\u8be2\u5b57\u7b26\u4e32\u6765\u533a\u5206\u4ea7\u54c1\u3002 \u8fd9\u79cd\u65b9\u6cd5\u8981\u5b9e\u7528\u5f97\u591a\uff0c\u4f46\u60a8\u6700\u7ec8\u4f1a\u5f97\u5230\u4e00\u4e9b\u96be\u770b\u7684 URL\uff0c\u4f8b\u5982\u201c\/product\uff1fname=big-widget\u201c \u6216 \u201d\/product\uff1fid=12\u201c \u7684 API \u7248\u672c\u3002<\/p>\n<\/li>\n<\/ul>\n
Definition<\/strong> The query string is part of a URL containing additional data that doesn\u2019t fit in the path. It isn\u2019t used by the routing infrastructure to identify which handler to execute, but ASP.NET Core can extract values from the query string automatically in a process called model binding, as you\u2019ll see in chapter 7. The query string in the preceding example is id=12.
\n\u5b9a\u4e49<\/strong> \u67e5\u8be2\u5b57\u7b26\u4e32\u662f URL \u7684\u4e00\u90e8\u5206\uff0c\u5176\u4e2d\u5305\u542b\u4e0d\u9002\u5408\u8def\u5f84\u7684\u5176\u4ed6\u6570\u636e\u3002\u8def\u7531\u57fa\u7840\u8bbe\u65bd\u4e0d\u4f7f\u7528\u5b83\u6765\u6807\u8bc6\u8981\u6267\u884c\u7684\u5904\u7406\u7a0b\u5e8f\uff0c\u4f46 ASP.NET Core \u53ef\u4ee5\u5728\u79f0\u4e3a\u6a21\u578b\u7ed1\u5b9a\u7684\u8fc7\u7a0b\u4e2d\u81ea\u52a8\u4ece\u67e5\u8be2\u5b57\u7b26\u4e32\u4e2d\u63d0\u53d6\u503c\uff0c\u5982\u7b2c 7 \u7ae0\u6240\u793a\u3002\u524d\u9762\u793a\u4f8b\u4e2d\u7684\u67e5\u8be2\u5b57\u7b26\u4e32\u4e3a id=12\u3002<\/p>\nWith routing, you can have a single endpoint handler that can handle multiple URLs without having to resort to ugly query strings. From the point of the view of the endpoint handler, the query string and routing approaches are similar; the handler returns the results for the correct product dynamically as appropriate. The difference is that with routing, you can completely customize the URLs, as shown in figure 6.2. This feature gives you much more flexibility and can be important in real-life applications for search engine optimization (SEO).<\/p>\n
\u901a\u8fc7\u8def\u7531\uff0c\u60a8\u53ef\u4ee5\u62e5\u6709\u4e00\u4e2a\u53ef\u4ee5\u5904\u7406\u591a\u4e2a URL \u7684\u7ec8\u7aef\u8282\u70b9\u5904\u7406\u7a0b\u5e8f\uff0c\u800c\u4e0d\u5fc5\u6c42\u52a9\u4e8e\u96be\u61c2\u7684\u67e5\u8be2\u5b57\u7b26\u4e32\u3002\u4ece\u7aef\u70b9\u7684\u89c6\u89d2handler\uff0c\u5219\u67e5\u8be2\u5b57\u7b26\u4e32\u548c\u8def\u7531\u65b9\u6cd5\u7c7b\u4f3c;\u5904\u7406\u7a0b\u5e8f\u4f1a\u6839\u636e\u9700\u8981\u52a8\u6001\u8fd4\u56de\u6b63\u786e\u4ea7\u54c1\u7684\u7ed3\u679c\u3002\u533a\u522b\u5728\u4e8e\uff0c\u4f7f\u7528\u8def\u7531\uff0c\u60a8\u53ef\u4ee5\u5b8c\u5168\u81ea\u5b9a\u4e49 URL\uff0c\u5982\u56fe 6.2 \u6240\u793a\u3002\u6b64\u529f\u80fd\u4e3a\u60a8\u63d0\u4f9b\u4e86\u66f4\u5927\u7684\u7075\u6d3b\u6027\uff0c\u5e76\u4e14\u5728\u641c\u7d22\u5f15\u64ce\u4f18\u5316 \uff08SEO\uff09 \u7684\u5b9e\u9645\u5e94\u7528\u7a0b\u5e8f\u4e2d\u53ef\u80fd\u5f88\u91cd\u8981\u3002<\/p>\n
Note<\/strong> With the flexibility of routing, you can encode the hierarchy of your site properly in your URLs, as described in Google\u2019s SEO starter guide at http:\/\/mng.bz\/EQ2J<\/a>.
\n\u6ce8\u610f<\/strong> \u501f\u52a9\u8def\u7531\u7684\u7075\u6d3b\u6027\uff0c\u60a8\u53ef\u4ee5\u5728 URL \u4e2d\u6b63\u786e\u7f16\u7801\u7f51\u7ad9\u7684\u5c42\u6b21\u7ed3\u6784\uff0c\u5982 http:\/\/mng.bz\/EQ2J<\/a> \u7684 Google SEO \u5165\u95e8\u6307\u5357\u4e2d\u6240\u8ff0\u3002<\/p>\n![\"\"](\"\/images\/aspnetcoreinaction\/0602.png\")
<\/p>\n
Figure 6.2 If you use static URL-based mapping, you need a different handler for every product in your product range. With a query string, you can use a single handler, and the query string contains the data. With routing, multiple URLs map to a single handler, and a dynamic parameter captures the difference in the URL.
\n\u56fe 6.2 \u5982\u679c\u4f7f\u7528\u57fa\u4e8e\u9759\u6001 URL \u7684\u6620\u5c04\uff0c\u5219\u4ea7\u54c1\u8303\u56f4\u4e2d\u7684\u6bcf\u4e2a\u4ea7\u54c1\u90fd\u9700\u8981\u4e0d\u540c\u7684\u5904\u7406\u7a0b\u5e8f\u3002\u4f7f\u7528\u67e5\u8be2\u5b57\u7b26\u4e32\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u5355\u4e2a\u5904\u7406\u7a0b\u5e8f\uff0c\u5e76\u4e14\u67e5\u8be2\u5b57\u7b26\u4e32\u5305\u542b\u6570\u636e\u3002\u4f7f\u7528\u8def\u7531\u65f6\uff0c\u591a\u4e2a URL \u6620\u5c04\u5230\u5355\u4e2a\u5904\u7406\u7a0b\u5e8f\uff0c\u5e76\u4e14\u52a8\u6001\u53c2\u6570\u6355\u83b7 URL \u4e2d\u7684\u5dee\u5f02\u3002<\/p>\n
As well as enabling dynamic URLs, routing fundamentally decouples the URLs in your application from the definition of your handlers.<\/p>\n
\u9664\u4e86\u542f\u7528\u52a8\u6001 URL \u4e4b\u5916\uff0c\u8def\u7531\u8fd8\u4ece\u6839\u672c\u4e0a\u5c06\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684 URL \u4e0e\u5904\u7406\u7a0b\u5e8f\u7684\u5b9a\u4e49\u5206\u79bb\u3002<\/p>\n
\nFile-system based routing
\n\u57fa\u4e8e\u6587\u4ef6\u7cfb\u7edf\u7684\u8def\u7531
\nIn one alternative to routing, the location of a handler on disk dictates the URL you use to invoke it. The downside of this approach is that if you want to change an exposed URL, you also need to change the location of the handler on disk.
\n\u5728\u8def\u7531\u7684\u53e6\u4e00\u79cd\u66ff\u4ee3\u65b9\u6cd5\u4e2d\uff0c\u5904\u7406\u7a0b\u5e8f\u5728\u78c1\u76d8\u4e0a\u7684\u4f4d\u7f6e\u51b3\u5b9a\u4e86\u7528\u4e8e\u8c03\u7528\u5b83\u7684 URL\u3002\u8fd9\u79cd\u65b9\u6cd5\u7684\u7f3a\u70b9\u662f\uff0c\u5982\u679c\u8981\u66f4\u6539\u516c\u5f00\u7684 URL\uff0c\u8fd8\u9700\u8981\u66f4\u6539\u5904\u7406\u7a0b\u5e8f\u5728\u78c1\u76d8\u4e0a\u7684\u4f4d\u7f6e\u3002
\nThis file-based approach may sound like a strange choice, but it has many advantages for some apps, primarily in terms of simplicity. As you\u2019ll see in part 2, Razor Pages is partially file-based but also uses routing to get the best of both worlds!
\n\u8fd9\u79cd\u57fa\u4e8e\u6587\u4ef6\u7684\u65b9\u6cd5\u542c\u8d77\u6765\u53ef\u80fd\u5f88\u5947\u602a\uff0c\u4f46\u5bf9\u4e8e\u67d0\u4e9b\u5e94\u7528\u7a0b\u5e8f\u6765\u8bf4\uff0c\u5b83\u6709\u5f88\u591a\u4f18\u70b9\uff0c\u4e3b\u8981\u662f\u5728\u7b80\u5355\u6027\u65b9\u9762\u3002\u6b63\u5982\u60a8\u5c06\u5728\u7b2c 2 \u90e8\u5206\u4e2d\u770b\u5230\u7684\u90a3\u6837\uff0cRazor Pages \u90e8\u5206\u57fa\u4e8e\u6587\u4ef6\uff0c\u4f46\u4e5f\u4f7f\u7528\u8def\u7531\u6765\u83b7\u5f97\u4e24\u5168\u5176\u7f8e\u7684\u6548\u679c\uff01<\/p>\n<\/blockquote>\n
With routing it\u2019s easy to modify your exposed URLs without changing any filenames or locations. You can also use routing to create friendlier URLs for users, which can improve discovery and \u201chackability.\u201d All of the following routes could point to the same handler:<\/p>\n
\u901a\u8fc7\u8def\u7531\uff0c\u53ef\u4ee5\u8f7b\u677e\u4fee\u6539\u516c\u5f00\u7684 URL\uff0c\u800c\u65e0\u9700\u66f4\u6539\u4efb\u4f55\u6587\u4ef6\u540d\u6216\u4f4d\u7f6e\u3002\u60a8\u8fd8\u53ef\u4ee5\u4f7f\u7528\u8def\u7531\u4e3a\u7528\u6237\u521b\u5efa\u66f4\u53cb\u597d\u7684 URL\uff0c\u8fd9\u53ef\u4ee5\u63d0\u9ad8\u53d1\u73b0\u548c\u201c\u53ef\u9ed1\u5ba2\u653b\u51fb\u6027\u201d\u3002\u4ee5\u4e0b\u6240\u6709\u8def\u7531\u90fd\u53ef\u4ee5\u6307\u5411\u540c\u4e00\u4e2a\u5904\u7406\u7a0b\u5e8f\uff1a<\/p>\n
\n- \/rates\/view\/1<\/li>\n
- \/rates\/view\/USD<\/li>\n
- \/rates\/current-exchange-rate\/USD<\/li>\n
- \/current-exchange-rate-for-USD<\/li>\n<\/ul>\n
This level of customization isn\u2019t often necessary, but it\u2019s quite useful to have the capability to customize your app\u2019s URLs when you need it. In the next section we\u2019ll look at how routing works in practice in ASP.NET Core.<\/p>\n
\u8fd9\u79cd\u7ea7\u522b\u7684\u81ea\u5b9a\u4e49\u901a\u5e38\u4e0d\u662f\u5fc5\u9700\u7684\uff0c\u4f46\u80fd\u591f\u5728\u9700\u8981\u65f6\u81ea\u5b9a\u4e49\u5e94\u7528\u7a0b\u5e8f\u7684 URL \u975e\u5e38\u6709\u7528\u3002\u5728\u4e0b\u4e00\u8282\u4e2d\uff0c\u6211\u4eec\u5c06\u4e86\u89e3 ASP.NET Core \u4e2d\u7684\u8def\u7531\u5b9e\u9645\u5de5\u4f5c\u539f\u7406\u3002<\/p>\n
6.2 Endpoint routing in ASP.NET Core<\/h2>\n6.2 ASP.NET Core \u4e2d\u7684\u7ec8\u7aef\u8282\u70b9\u8def\u7531<\/h2>\n
In this section I describe how endpoint routing works in ASP.NET Core, specifically with respect to minimal APIs and the middleware pipeline. In chapter 14 you\u2019ll learn how routing is used with Razor Pages and the ASP.NET Core MVC framework.<\/p>\n
\u5728\u672c\u8282\u4e2d\uff0c\u6211\u5c06\u4ecb\u7ecd\u7ec8\u7aef\u8282\u70b9\u8def\u7531\u5728 ASP.NET Core \u4e2d\u7684\u5de5\u4f5c\u539f\u7406\uff0c\u7279\u522b\u662f\u5173\u4e8e\u6700\u5c0f API \u548c\u4e2d\u95f4\u4ef6\u7ba1\u9053\u3002\u5728\u7b2c 14 \u7ae0\u4e2d\uff0c\u60a8\u5c06\u4e86\u89e3\u5982\u4f55\u5c06\u8def\u7531\u4e0e Razor Pages \u548c ASP.NET Core MVC \u6846\u67b6\u4e00\u8d77\u4f7f\u7528\u3002<\/p>\n
Routing has been part of ASP.NET Core since its inception, but it has been through some big changes. In ASP.NET Core 2.0 and 2.1, routing was restricted to Razor Pages and the ASP.NET Core MVC framework. There was no dedicated routing middleware in the middleware pipeline; routing happened only within Razor Pages or MVC components.<\/p>\n
\u8def\u7531\u81ea\u6210\u7acb\u4ee5\u6765\u4e00\u76f4\u662f ASP.NET Core \u7684\u4e00\u90e8\u5206\uff0c\u4f46\u5b83\u7ecf\u5386\u4e86\u4e00\u4e9b\u91cd\u5927\u53d8\u5316\u3002\u5728 ASP.NET Core \u4e2d2.0 \u548c 2.1 \u4e2d\uff0c\u8def\u7531\u4ec5\u9650\u4e8e Razor Pages \u548c ASP.NET Core MVC \u6846\u67b6\u3002\u4e2d\u95f4\u4ef6\u7ba1\u9053\u4e2d\u6ca1\u6709\u4e13\u7528\u7684\u8def\u7531\u4e2d\u95f4\u4ef6;\u8def\u7531\u4ec5\u5728 Razor Pages \u6216 MVC \u7ec4\u4ef6\u4e2d\u53d1\u751f\u3002<\/p>\n
Unfortunately, restricting routing to the MVC and Razor Pages infrastructure made some things a bit messy. Some cross-cutting concerns, such as authorization, were restricted to the MVC infrastructure and were hard to use from other middleware in your application. That restriction caused inevitable duplication, which wasn\u2019t ideal.<\/p>\n
\u9057\u61be\u7684\u662f\uff0c\u5c06\u8def\u7531\u5230 MVC \u548c Razor Pages \u57fa\u7840\u7ed3\u6784\u4f1a\u4f7f\u67d0\u4e9b\u4e8b\u60c5\u53d8\u5f97\u6709\u70b9\u6df7\u4e71\u3002\u4e00\u4e9b\u6a2a\u5207\u5173\u6ce8\u70b9\uff08\u5982\u6388\u6743\uff09\u4ec5\u9650\u4e8e MVC \u57fa\u7840\u8bbe\u65bd\uff0c\u5e76\u4e14\u5f88\u96be\u4ece\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684\u5176\u4ed6\u4e2d\u95f4\u4ef6\u4e2d\u4f7f\u7528\u3002\u8fd9\u79cd\u9650\u5236\u5bfc\u81f4\u4e86\u4e0d\u53ef\u907f\u514d\u7684\u91cd\u590d\uff0c\u8fd9\u5e76\u4e0d\u7406\u60f3\u3002<\/p>\n
ASP.NET Core 3.0 introduced a new routing system: endpoint routing. Endpoint routing makes the routing system a more fundamental feature of ASP.NET Core and no longer ties it to the MVC infrastructure. Now Razor Pages, MVC, and other middleware can all use the same routing system. .NET 7 continues to use the same endpoint routing system, which is integral to the minimal API functionality that was introduced in .NET 6.<\/p>\n
ASP.NET Core 3.0 \u5f15\u5165\u4e86\u4e00\u4e2a\u65b0\u7684\u8def\u7531\u7cfb\u7edf\uff1a\u7aef\u70b9\u8def\u7531\u3002\u7aef\u70b9\u8def\u7531\u4f7f\u8def\u7531\u7cfb\u7edf\u6210\u4e3a ASP.NET Core \u7684\u66f4\u57fa\u672c\u529f\u80fd\uff0c\u4e0d\u518d\u5c06\u5176\u7ed1\u5b9a\u5230 MVC \u57fa\u7840\u8bbe\u65bd\u3002\u73b0\u5728\uff0cRazor Pages\u3001MVC \u548c\u5176\u4ed6\u4e2d\u95f4\u4ef6\u90fd\u53ef\u4ee5\u4f7f\u7528\u76f8\u540c\u7684\u8def\u7531\u7cfb\u7edf\u3002.NET 7 \u7ee7\u7eed\u4f7f\u7528\u76f8\u540c\u7684\u7ec8\u7ed3\u70b9\u8def\u7531\u7cfb\u7edf\uff0c\u8fd9\u662f .NET 6 \u4e2d\u5f15\u5165\u7684\u6700\u5c0f API \u529f\u80fd\u4e0d\u53ef\u6216\u7f3a\u7684\u4e00\u90e8\u5206\u3002<\/p>\n
Endpoint routing is fundamental to all but the simplest ASP.NET Core apps. It\u2019s implemented with two pieces of middleware, which you\u2019ve already seen:<\/p>\n
\u7aef\u70b9\u8def\u7531\u662f\u9664\u6700\u7b80\u5355\u7684 ASP.NET Core \u5e94\u7528\u7a0b\u5e8f\u4e4b\u5916\u7684\u6240\u6709\u5e94\u7528\u7a0b\u5e8f\u7684\u57fa\u7840\u3002\u5b83\u662f\u901a\u8fc7\u4e24\u4e2a\u4e2d\u95f4\u4ef6\u5b9e\u73b0\u7684\uff0c\u60a8\u5df2\u7ecf\u770b\u5230\u4e86\uff1a<\/p>\n
\n- \n
EndpointRoutingMiddleware\u2014This middleware chooses which registered endpoints execute for a given request at runtime. To make it easier to distinguish between the two types of middleware, I\u2019ll be referring to this middleware as the RoutingMiddleware throughout this book.
\nEndpointRoutingMiddleware \u2014 \u6b64\u4e2d\u95f4\u4ef6\u9009\u62e9\u5728\u8fd0\u884c\u65f6\u4e3a\u7ed9\u5b9a\u8bf7\u6c42\u6267\u884c\u54ea\u4e9b\u5df2\u6ce8\u518c\u7684\u7ec8\u7aef\u8282\u70b9\u3002\u4e3a\u4e86\u66f4\u5bb9\u6613\u533a\u5206\u8fd9\u4e24\u79cd\u7c7b\u578b\u7684\u4e2d\u95f4\u4ef6\uff0c\u6211\u5728\u672c\u4e66\u4e2d\u5c06\u6b64\u4e2d\u95f4\u4ef6\u79f0\u4e3a RoutingMiddleware\u3002<\/p>\n<\/li>\n
- \n
EndpointMiddleware\u2014This middleware is typically placed at the end of your middleware pipeline. The middleware executes the endpoint selected by the RoutingMiddleware at runtime.
\nEndpointMiddleware \u2014 \u6b64\u4e2d\u95f4\u4ef6\u901a\u5e38\u4f4d\u4e8e\u4e2d\u95f4\u4ef6\u7ba1\u9053\u7684\u672b\u5c3e\u3002\u4e2d\u95f4\u4ef6\u5728\u8fd0\u884c\u65f6\u6267\u884c RoutingMiddleware \u9009\u62e9\u7684\u7aef\u70b9\u3002<\/p>\n<\/li>\n<\/ul>\n
You register the endpoints in your application by calling Map* functions on an IEndpointRouteBuilder instance. In .NET 7 apps, this instance typically is a WebApplication instance but doesn\u2019t have to be, as you\u2019ll see in chapter 30.<\/p>\n
\u60a8\u53ef\u4ee5\u901a\u8fc7\u5728 IEndpointRouteBuilder \u5b9e\u4f8b\u4e0a\u8c03\u7528 Map* \u51fd\u6570\u5728\u5e94\u7528\u7a0b\u5e8f\u4e2d\u6ce8\u518c\u7ec8\u7aef\u8282\u70b9\u3002\u5728 .NET 7 \u5e94\u7528\u7a0b\u5e8f\u4e2d\uff0c\u6b64\u5b9e\u4f8b\u901a\u5e38\u662f Web- Application \u5b9e\u4f8b\uff0c\u4f46\u5e76\u975e\u5fc5\u987b\u5982\u6b64\uff0c\u5982\u7b2c 30 \u7ae0\u6240\u793a\u3002<\/p>\n
Definition<\/em> An endpoint in ASP.NET Core is a handler that returns a response. Each endpoint is associated with a URL pattern. Depending on the type of application you\u2019re building, minimal API handlers, Razor Page handlers, or MVC controller action methods typically make up the bulk of the endpoints in an application. You can also use simple middleware as an endpoint or a health-check endpoint, for example.
\n\u5b9a\u4e49<\/em> ASP.NET Core \u4e2d\u7684\u7ec8\u7aef\u8282\u70b9\u662f\u8fd4\u56de\u54cd\u5e94\u7684\u5904\u7406\u7a0b\u5e8f\u3002\u6bcf\u4e2a\u7aef\u70b9\u90fd\u4e0e\u4e00\u4e2a URL \u6a21\u5f0f\u76f8\u5173\u8054\u3002\u6839\u636e\u8981\u751f\u6210\u7684\u5e94\u7528\u7a0b\u5e8f\u7c7b\u578b\uff0c\u6700\u5c11\u7684 API \u5904\u7406\u7a0b\u5e8f\u3001Razor Page \u5904\u7406\u7a0b\u5e8f\u6216 MVC \u63a7\u5236\u5668\u4f5c\u65b9\u6cd5\u901a\u5e38\u6784\u6210\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684\u5927\u90e8\u5206\u7ec8\u7ed3\u70b9\u3002\u4f8b\u5982\uff0c\u60a8\u8fd8\u53ef\u4ee5\u4f7f\u7528\u7b80\u5355\u7684\u4e2d\u95f4\u4ef6\u4f5c\u4e3a\u7ec8\u7aef\u8282\u70b9\uff0c\u6216\u8005\u60a8\u53ef\u4ee5\u4f7f\u7528\u8fd0\u884c\u72b6\u51b5\u68c0\u67e5\u7ec8\u7aef\u8282\u70b9\u3002<\/p>\nWebApplication implements IEndpointRouteBuilder, so you can register endpoints on it directly. Listing 6.1 shows how you\u2019d register several endpoints:<\/p>\n
WebApplication \u5b9e\u73b0 IEndpointRouteBuilder\uff0c\u56e0\u6b64\u60a8\u53ef\u4ee5\u76f4\u63a5\u5728\u5176\u4e0a\u6ce8\u518c\u7aef\u70b9\u3002\u6e05\u5355 6.1 \u5c55\u793a\u4e86\u5982\u4f55\u6ce8\u518c\u591a\u4e2a\u7aef\u70b9\uff1a<\/p>\n
\n- \n
A minimal API handler using MapGet(), as you\u2019ve seen in previous chapters.
\n\u4f7f\u7528 MapGet\uff08\uff09 \u7684\u6700\u5c0f API \u5904\u7406\u7a0b\u5e8f\uff0c\u5982\u524d\u51e0\u7ae0\u6240\u793a\u3002<\/p>\n<\/li>\n
- \n
A health-check endpoint using MapHealthChecks(). You can read more about health checks at http:\/\/mng.bz\/N2YD<\/a>.
\n\u4f7f\u7528 MapHealthChecks\uff08\uff09 \u7684\u8fd0\u884c\u72b6\u51b5\u68c0\u67e5\u7ec8\u7aef\u8282\u70b9\u3002\u60a8\u53ef\u4ee5\u5728 http:\/\/mng.bz\/N2YD<\/a> \u4e0a\u9605\u8bfb\u6709\u5173\u8fd0\u884c\u72b6\u51b5\u68c0\u67e5\u7684\u66f4\u591a\u4fe1\u606f\u3002<\/p>\n<\/li>\n- \n
All Razor Pages endpoints in the application using MapRazorPages(). You\u2019ll learn more about routing with Razor Pages in chapter 14.
\n\u4f7f\u7528 MapRazorPages\uff08\uff09 \u7684\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684\u6240\u6709 Razor Pages \u7ec8\u7ed3\u70b9\u3002\u60a8\u5c06\u5728\u7b2c 14 \u7ae0\u4e2d\u4e86\u89e3\u6709\u5173\u4f7f\u7528 Razor Pages \u8fdb\u884c\u8def\u7531\u7684\u66f4\u591a\u4fe1\u606f\u3002<\/p>\n<\/li>\n<\/ul>\n
Listing 6.1 Registering multiple endpoints with WebApplication
\n\u6e05\u5355 6.1 \u4f7f\u7528 \u6ce8\u518c\u591a\u4e2a\u7aef\u70b9Web\u5e94\u7528\u7a0b\u5e8f<\/p>\n
\nWebApplicationBuilder builder = WebApplication.CreateBuilder(args);\nbuilder.Services.AddHealthChecks(); \/\/ \u2776\nbuilder.Services.AddRazorPages(); \/\/ \u2776\n\nWebApplication app = builder.Build();\n\napp.MapGet("\/test", () => "Hello world!"); \/\/ \u2777\napp.MapHealthChecks("\/healthz"); \/\/ \u2778\napp.MapRazorPages(); \/\/ \u2779\n\napp.Run();\n<\/pre>\n\u2776 Adds the services required by the health-check middleware and Razor Pages
\n\u6dfb\u52a0\u8fd0\u884c\u72b6\u51b5\u68c0\u67e5\u4e2d\u95f4\u4ef6\u548c Razor Pages \u6240\u9700\u7684\u670d\u52a1<\/p>\n
\u2777 Registers a minimal API endpoint that returns \u201cHello World!\u201d at the route \/test
\n\u6ce8\u518c\u4e00\u4e2a\u6700\u5c0f\u7684 API \u7aef\u70b9\uff0c\u8be5\u7aef\u70b9\u5728\u8def\u7531 \/test \u4e2d\u8fd4\u56de \u201cHello World\uff01\u201d<\/p>\n
\u2778 Registers a health-check endpoint at the route \/healthz
\n\u5728\u8def\u7531 \/healthz \u4e2d\u6ce8\u518c\u4e00\u4e2a\u5065\u5eb7\u68c0\u67e5\u7aef\u70b9<\/p>\n
\u2779 Registers all the Razor Pages in your application as endpoints
\n\u5c06\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684\u6240\u6709 Razor Pages \u6ce8\u518c\u4e3a\u7aef\u70b9<\/p>\n
Each endpoint is associated with a route template that defines which URLs the endpoint should match. You can see two route templates, "\/healthz" and "\/test", in listing 6.1.<\/p>\n
\u6bcf\u4e2a\u7ec8\u7aef\u8282\u70b9\u90fd\u4e0e\u4e00\u4e2a\u8def\u7531\u6a21\u677f\u76f8\u5173\u8054\uff0c\u8be5\u6a21\u677f\u5b9a\u4e49\u7ec8\u7aef\u8282\u70b9\u5e94\u5339\u914d\u7684 URL\u3002\u5728\u6e05\u5355 6.1 \u4e2d\u53ef\u4ee5\u770b\u5230\u4e24\u4e2a\u8def\u7531\u6a21\u677f\uff0c\u201c\/healthz\u201d \u548c \u201c\/test\u201d\u3002<\/p>\n
DEFINITION<\/b> A route template is a URL pattern that is used to match against request URLs, which are strings of fixed values, such as "\/test" in the previous listing. They can also contain placeholders for variables, as you\u2019ll see in section 6.3.
\n\u5b9a\u4e49\uff1a \u8def\u7531\u6a21\u677f\u662f\u4e00\u79cd URL \u6a21\u5f0f\uff0c\u7528\u4e8e\u5339\u914d\u8bf7\u6c42 URL\uff0c\u8bf7\u6c42 URL \u662f\u56fa\u5b9a\u503c\u7684\u5b57\u7b26\u4e32\uff0c\u5982\u4e0a\u4e00\u4e2a\u5217\u8868\u4e2d\u7684 \u201c\/test\u201d\u3002 \u5b83\u4eec\u8fd8\u53ef\u4ee5\u5305\u542b\u53d8\u91cf\u7684\u5360\u4f4d\u7b26\uff0c\u5982 6.3 \u8282\u6240\u793a\u3002<\/p>\n
The WebApplication stores the registered routes and endpoints in a dictionary that\u2019s shared by the RoutingMiddleware and the EndpointMiddleware.<\/p>\n
WebApplication \u5c06\u6ce8\u518c\u7684\u8def\u7531\u548c\u7ec8\u7aef\u8282\u70b9\u5b58\u50a8\u5728 RoutingMiddleware \u548c EndpointMiddleware \u5171\u4eab\u7684\u5b57\u5178\u4e2d\u3002<\/p>\n
TIP<\/b> By default, WebApplication automatically adds the RoutingMiddleware to the start of the middleware and EndpointMiddleware to the end of the middleware pipeline, though you can override the location in the pipeline by calling UseRouting() or UseEndpoints(). See section 4.2.3 for more details about automatically added middleware.
\n\u63d0\u793a\uff1a \u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0cWebApplication \u4f1a\u81ea\u52a8\u5c06 RoutingMiddleware \u6dfb\u52a0\u5230\u4e2d\u95f4\u4ef6\u7684\u5f00\u5934\uff0c\u5c06 EndpointMiddleware \u6dfb\u52a0\u5230\u4e2d\u95f4\u4ef6\u7ba1\u9053\u7684\u672b\u5c3e\uff0c\u4f46\u60a8\u53ef\u4ee5\u901a\u8fc7\u8c03\u7528 UseRouting\uff08\uff09 \u6216 UseEndpoints\uff08\uff09 \u6765\u8986\u76d6\u7ba1\u9053\u4e2d\u7684\u4f4d\u7f6e\u3002\u6709\u5173\u81ea\u52a8\u6dfb\u52a0\u7684\u4e2d\u95f4\u4ef6\u7684\u66f4\u591a\u8be6\u7ec6\u4fe1\u606f\uff0c\u8bf7\u53c2\u89c1 Section 4.2.3\u3002<\/p>\n
At runtime, the RoutingMiddleware compares an incoming request with the routes registered in the dictionary. If the RoutingMiddleware finds a matching endpoint, it makes a note of which endpoint was selected and attaches that to the request\u2019s HttpContext object. Then it calls the next middleware in the pipeline. When the request reaches the EndpointMiddleware, the middleware checks to see which endpoint was selected and executes the endpoint (and any associated endpoint filters), as shown in figure 6.3.<\/p>\n
\u5728\u8fd0\u884c\u65f6\uff0cRoutingMiddleware \u5c06\u4f20\u5165\u8bf7\u6c42\u4e0e\u5b57\u5178\u4e2d\u6ce8\u518c\u7684\u8def\u7531\u8fdb\u884c\u6bd4\u8f83\u3002\u5982\u679c RoutingMiddleware \u627e\u5230\u5339\u914d\u7684\u7aef\u70b9\uff0c\u5b83\u4f1a\u8bb0\u4e0b\u9009\u62e9\u4e86\u54ea\u4e2a\u7aef\u70b9\uff0c\u5e76\u5c06\u5176\u9644\u52a0\u5230\u8bf7\u6c42\u7684 HttpContext \u5bf9\u8c61\u3002\u7136\u540e\uff0c\u5b83\u4f1a\u8c03\u7528\u7ba1\u9053\u4e2d\u7684\u4e0b\u4e00\u4e2a\u4e2d\u95f4\u4ef6\u3002\u5f53\u8bf7\u6c42\u5230\u8fbe EndpointMiddleware \u65f6\uff0c\u4e2d\u95f4\u4ef6\u4f1a\u68c0\u67e5\u9009\u62e9\u54ea\u4e2a\u7aef\u70b9\u5e76\u6267\u884c\u8be5\u7aef\u70b9\uff08\u4ee5\u53ca\u4efb\u4f55\u5173\u8054\u7684\u7aef\u70b9\u8fc7\u6ee4\u5668\uff09\uff0c\u5982\u56fe 6.3 \u6240\u793a\u3002<\/p>\n
![\"\"](\"\/images\/aspnetcoreinaction\/0603.png\")
<\/p>\n
Figure 6.3 Endpoint routing uses a two-step process. The RoutingMiddleware selects which endpoint to execute, and the EndpointMiddleware executes it. If the request URL doesn\u2019t match a route template, the endpoint middleware won\u2019t generate a response.
\n\u56fe 6.3 \u7ec8\u7aef\u8282\u70b9\u8def\u7531\u4f7f\u7528\u4e24\u6b65\u8fc7\u7a0b\u3002RoutingMiddleware \u9009\u62e9\u8981\u6267\u884c\u7684\u7aef\u70b9\uff0cEndpointMiddleware \u6267\u884c\u5b83\u3002\u5982\u679c\u8bf7\u6c42 URL \u4e0e\u8def\u7531\u6a21\u677f\u4e0d\u5339\u914d\uff0c\u5219\u7ec8\u7aef\u8282\u70b9\u4e2d\u95f4\u4ef6\u4e0d\u4f1a\u751f\u6210\u54cd\u5e94\u3002<\/p>\n
If the request URL doesn\u2019t match a route template, the RoutingMiddleware doesn\u2019t select an endpoint, but the request still continues down the middleware pipeline. As no endpoint is selected, the EndpointMiddleware silently ignores the request and passes it to the next middleware in the pipeline. The EndpointMiddleware is typically the final middleware in the pipeline, so the \u201cnext\u201d middleware is normally the dummy middleware that always returns a 404 Not Found response, as you saw in chapter 4.<\/p>\n
\u5982\u679c\u8bf7\u6c42 URL \u4e0e\u8def\u7531\u6a21\u677f\u4e0d\u5339\u914d\uff0c\u5219 RoutingMiddleware \u4e0d\u4f1a\u9009\u62e9\u7ec8\u7aef\u8282\u70b9\uff0c\u4f46\u8bf7\u6c42\u4ecd\u4f1a\u7ee7\u7eed\u6cbf\u4e2d\u95f4\u4ef6\u7ba1\u9053\u5411\u4e0b\u79fb\u52a8\u3002\u7531\u4e8e\u672a\u9009\u62e9\u4efb\u4f55\u7ec8\u7aef\u8282\u70b9\uff0c\u56e0\u6b64 EndpointMiddleware \u4f1a\u9759\u9ed8\u5ffd\u7565\u8be5\u8bf7\u6c42\u5e76\u5c06\u5176\u4f20\u9012\u7ed9\u7ba1\u9053\u4e2d\u7684\u4e0b\u4e00\u4e2a\u4e2d\u95f4\u4ef6\u3002EndpointMiddleware \u901a\u5e38\u662f\u7ba1\u9053\u4e2d\u7684\u6700\u540e\u4e00\u4e2a\u4e2d\u95f4\u4ef6\uff0c\u56e0\u6b64 \u201cnext\u201d \u4e2d\u95f4\u4ef6\u901a\u5e38\u662f\u59cb\u7ec8\u8fd4\u56de 404 Not Found \u54cd\u5e94\u7684\u865a\u62df\u4e2d\u95f4\u4ef6\uff0c\u5982\u7b2c 4 \u7ae0\u6240\u793a\u3002<\/p>\n
TIP<\/b> If the request URL doesn\u2019t match a route template, no endpoint is selected or executed. The whole middleware pipeline is still executed, but typically a 404 response is returned when the request reaches the dummy 404 middleware.
\n\u63d0\u793a\uff1a \u5982\u679c\u8bf7\u6c42 URL \u4e0e\u8def\u7531\u6a21\u677f\u4e0d\u5339\u914d\uff0c\u5219\u4e0d\u4f1a\u9009\u62e9\u6216\u6267\u884c\u4efb\u4f55\u7ec8\u7aef\u8282\u70b9\u3002\u6574\u4e2a\u4e2d\u95f4\u4ef6\u7ba1\u9053\u4ecd\u7136\u4f1a\u6267\u884c\uff0c\u4f46\u5f53\u8bf7\u6c42\u5230\u8fbe\u865a\u62df 404 \u4e2d\u95f4\u4ef6\u65f6\uff0c\u901a\u5e38\u4f1a\u8fd4\u56de 404 \u54cd\u5e94\u3002<\/p>\n
The advantage of having two separate pieces of middleware to handle this process may not be obvious at first blush. Figure 6.3 hinted at the main benefit: all middleware placed after the RoutingMiddleware can see which endpoint is going to be executed before it is.<\/p>\n
\u4f7f\u7528\u4e24\u4e2a\u5355\u72ec\u7684\u4e2d\u95f4\u4ef6\u6765\u5904\u7406\u6b64\u8fc7\u7a0b\u7684\u4f18\u52bf\u4e4d\u4e00\u770b\u53ef\u80fd\u5e76\u4e0d\u660e\u663e\u3002\u56fe 6.3 \u6697\u793a\u4e86\u4e3b\u8981\u7684\u597d\u5904\uff1a\u6240\u6709\u653e\u5728 RoutingMiddleware \u540e\u9762\u7684\u4e2d\u95f4\u4ef6\u90fd\u53ef\u4ee5\u5728\u6267\u884c\u4e4b\u524d\u770b\u5230\u54ea\u4e2a\u7aef\u70b9\u5c06\u88ab\u6267\u884c\u3002<\/p>\n
NOTE<\/b> Only middleware placed after the RoutingMiddleware can detect which endpoint is going to be executed.
\n\u6ce8\u610f\uff1a \u53ea\u6709\u653e\u5728 RoutingMiddleware \u4e4b\u540e\u7684 middleware \u624d\u80fd\u68c0\u6d4b\u5230\u5c06\u8981\u6267\u884c\u7684\u7aef\u70b9\u3002<\/p>\n
Figure 6.4 shows a more realistic middleware pipeline in which middleware is placed both before the RoutingMiddleware and between the RoutingMiddleware and the EndpointMiddleware.<\/p>\n
\u56fe 6.4 \u663e\u793a\u4e86\u4e00\u4e2a\u66f4\u771f\u5b9e\u7684\u4e2d\u95f4\u4ef6\u7ba1\u9053\uff0c\u5176\u4e2d\u4e2d\u95f4\u4ef6\u653e\u7f6e\u5728 RoutingMiddleware \u4e4b\u524d\u4ee5\u53ca RoutingMiddleware \u548c EndpointMiddleware \u4e4b\u95f4\u3002<\/p>\n
![\"\"](\"\/images\/aspnetcoreinaction\/0604.png\")
<\/p>\n
Figure 6.4 Middleware placed before the routing middleware doesn\u2019t know which endpoint the routing middleware will select. Middleware placed between the routing middleware and the endpoint middleware can see the selected endpoint.
\n\u56fe 6.4 \u653e\u7f6e\u5728\u8def\u7531\u4e2d\u95f4\u4ef6\u524d\u9762\u7684\u4e2d\u95f4\u4ef6\u4e0d\u77e5\u9053\u8def\u7531\u4e2d\u95f4\u4ef6\u5c06\u9009\u62e9\u54ea\u4e2a\u7aef\u70b9\u3002\u653e\u7f6e\u5728\u8def\u7531\u4e2d\u95f4\u4ef6\u548c\u7ec8\u7aef\u8282\u70b9\u4e2d\u95f4\u4ef6\u4e4b\u95f4\u7684\u4e2d\u95f4\u4ef6\u53ef\u4ee5\u770b\u5230\u6240\u9009\u7ec8\u7aef\u8282\u70b9\u3002<\/p>\n
The StaticFileMiddleware in figure 6.4 is placed before the RoutingMiddleware, so it executes before an endpoint is selected. Conversely, the AuthorizationMiddleware is placed after the RoutingMiddleware, so it can tell which minimal API endpoint will be executed eventually. In addition, it can access certain metadata about the endpoint, such as its name and the permissions required to access it.<\/p>\n
\u56fe 6.4 \u4e2d\u7684 StaticFileMiddleware \u4f4d\u4e8e RoutingMiddleware \u4e4b\u524d\uff0c\u56e0\u6b64\u5b83\u5728\u9009\u62e9\u7aef\u70b9\u4e4b\u524d\u6267\u884c\u3002\u76f8\u53cd\uff0cAuthorizationMiddleware \u4f4d\u4e8e RoutingMiddleware \u4e4b\u540e\uff0c\u56e0\u6b64\u5b83\u53ef\u4ee5\u5224\u65ad\u6700\u7ec8\u5c06\u6267\u884c\u54ea\u4e2a\u6700\u5c0f\u7684 API \u7aef\u70b9\u3002\u6b64\u5916\uff0c\u5b83\u8fd8\u53ef\u4ee5\u8bbf\u95ee\u6709\u5173\u7ec8\u7aef\u8282\u70b9\u7684\u67d0\u4e9b\u5143\u6570\u636e\uff0c\u4f8b\u5982\u5176\u540d\u79f0\u548c\u8bbf\u95ee\u7ec8\u7aef\u8282\u70b9\u6240\u9700\u7684\u6743\u9650\u3002<\/p>\n
TIP<\/b> The AuthorizationMiddleware needs to know which endpoint will be executed, so it must be placed after the RoutingMiddleware and before the EndpointMiddleware in your middleware pipeline. I discuss authorization in more detail in chapter 24.
\n\u63d0\u793a\uff1a AuthorizationMiddleware \u9700\u8981\u77e5\u9053\u5c06\u6267\u884c\u54ea\u4e2a\u7aef\u70b9\uff0c\u56e0\u6b64\u5b83\u5fc5\u987b\u653e\u5728\u4e2d\u95f4\u4ef6\u7ba1\u9053\u4e2d\u7684 RoutingMiddleware \u4e4b\u540e\u548c EndpointMiddleware \u4e4b\u524d\u3002\u6211\u5728\u7b2c 24 \u7ae0\u4e2d\u66f4\u8be6\u7ec6\u5730\u8ba8\u8bba\u4e86\u6388\u6743\u3002<\/p>\n
It\u2019s important to remember the different roles of the two types of routing middleware when building your application. If you have a piece of middleware that needs to know which endpoint (if any) a given request will execute, you need to make sure to place it after the RoutingMiddleware and before the EndpointMiddleware.<\/p>\n
\u5728\u6784\u5efa\u5e94\u7528\u7a0b\u5e8f\u65f6\uff0c\u8bf7\u52a1\u5fc5\u8bb0\u4f4f\u8fd9\u4e24\u79cd\u7c7b\u578b\u7684\u8def\u7531\u4e2d\u95f4\u4ef6\u7684\u4e0d\u540c\u89d2\u8272\u3002\u5982\u679c\u4f60\u6709\u4e00\u4e2a\u4e2d\u95f4\u4ef6\u9700\u8981\u77e5\u9053\u7ed9\u5b9a\u8bf7\u6c42\u5c06\u6267\u884c\u54ea\u4e2a\u7aef\u70b9\uff08\u5982\u679c\u6709\u7684\u8bdd\uff09\uff0c\u4f60\u9700\u8981\u786e\u4fdd\u5c06\u5176\u653e\u5728 RoutingMiddleware \u4e4b\u540e\u548c EndpointMiddleware \u4e4b\u524d\u3002<\/p>\n
TIP<\/b> If you want to place middleware before the RoutingMiddleware, such as the StaticFileMiddleware in figure 6.4, you need to override the automatic middleware added by WebApplication by calling UseRouting() at the appropriate point in your middleware pipeline. See listing 4.3 in chapter 4 for an example.
\n\u63d0\u793a\uff1a \u5982\u679c\u4f60\u60f3\u628a\u4e2d\u95f4\u4ef6\u653e\u5728 RoutingMiddleware \u4e4b\u524d\uff0c\u6bd4\u5982\u56fe 6.4 \u4e2d\u7684 StaticFileMiddleware\uff0c\u4f60\u9700\u8981\u5728\u4e2d\u95f4\u4ef6\u7ba1\u9053\u4e2d\u7684\u9002\u5f53\u4f4d\u7f6e\u8c03\u7528 UseRouting\uff08\uff09 \u6765\u8986\u76d6 WebApplication \u6dfb\u52a0\u7684\u81ea\u52a8\u4e2d\u95f4\u4ef6\u3002\u6709\u5173\u793a\u4f8b\uff0c\u8bf7\u53c2\u89c1\u7b2c 4 \u7ae0\u4e2d\u7684\u6e05\u5355 4.3\u3002<\/p>\n
I\u2019ve covered how the RoutingMiddleware and EndpointMiddleware interact to provide routing capabilities in ASP.NET Core, but we\u2019ve looked at only simple route templates so far. In the next section we\u2019ll look at some of the many features available with route templates.<\/p>\n
\u6211\u5df2\u7ecf\u4ecb\u7ecd\u4e86 RoutingMiddleware \u548c EndpointMiddleware \u5982\u4f55\u4ea4\u4e92\u4ee5\u5728 ASP.NET Core \u4e2d\u63d0\u4f9b\u8def\u7531\u529f\u80fd\uff0c\u4f46\u5230\u76ee\u524d\u4e3a\u6b62\uff0c\u6211\u4eec\u53ea\u4e86\u89e3\u4e86\u7b80\u5355\u7684\u8def\u7531\u6a21\u677f\u3002\u5728\u4e0b\u4e00\u8282\u4e2d\uff0c\u6211\u4eec\u5c06\u4e86\u89e3\u8def\u7531\u6a21\u677f\u63d0\u4f9b\u7684\u4f17\u591a\u529f\u80fd\u4e2d\u7684\u4e00\u4e9b\u3002<\/p>\n
6.3 Exploring the route template syntax<\/h2>\n6.3 \u63a2\u7d22\u8def\u7531\u6a21\u677f\u8bed\u6cd5<\/h2>\n
So far in this book we\u2019ve looked at simple route templates consisting of fixed values, such as \/person and \/test, as well as using a basic route parameter such as \/fruit\/{id}. In this section we explore the full range of features available in route templates, such as default values, optional segments, and constraints.<\/p>\n
\u5230\u76ee\u524d\u4e3a\u6b62\uff0c\u5728\u672c\u4e66\u4e2d\uff0c\u6211\u4eec\u5df2\u7ecf\u4e86\u89e3\u4e86\u7531\u56fa\u5b9a\u503c\u7ec4\u6210\u7684\u7b80\u5355\u8def\u7531\u6a21\u677f\uff0c\u4f8b\u5982 \/person \u548c \/test\uff0c\u4ee5\u53ca\u4f7f\u7528\u57fa\u672c\u8def\u7531\u53c2\u6570\uff0c\u4f8b\u5982\/fruit\/{id} \u4e2d\u3002\u5728\u672c\u8282\u4e2d\uff0c\u6211\u4eec\u5c06\u63a2\u8ba8\u8def\u7531\u6a21\u677f\u4e2d\u63d0\u4f9b\u7684\u5168\u90e8\u529f\u80fd\uff0c\u4f8b\u5982\u9ed8\u8ba4\u503c\u3001\u53ef\u9009\u5206\u6bb5\u548c\u7ea6\u675f\u3002<\/p>\n
6.3.1 Working with parameters and literal segments<\/h3>\n6.3.1 \u4f7f\u7528\u53c2\u6570\u548c\u6587\u672c\u6bb5<\/h3>\n
Route templates have a rich, flexible syntax. Figure 6.5, however, shows a simple example, similar to ones you\u2019ve already seen.<\/p>\n
\u8def\u7531\u6a21\u677f\u5177\u6709\u4e30\u5bcc\u3001\u7075\u6d3b\u7684\u8bed\u6cd5\u3002\u7136\u800c\uff0c\u56fe 6.5 \u663e\u793a\u4e86\u4e00\u4e2a\u7b80\u5355\u7684\u4f8b\u5b50\uff0c\u7c7b\u4f3c\u4e8e\u4f60\u5df2\u7ecf\u770b\u5230\u7684\u90a3\u4e9b\u3002<\/p>\n
![\"\"](\"\/images\/aspnetcoreinaction\/0605.png\")
<\/p>\n
Figure 6.5 A simple route template showing a literal segment and two required route parameters
\n\u56fe 6.5 \u4e00\u4e2a\u7b80\u5355\u7684\u8def\u7531\u6a21\u677f\uff0c\u5176\u4e2d\u663e\u793a\u4e86\u4e00\u4e2a\u6587\u672c\u6bb5\u548c\u4e24\u4e2a\u5fc5\u9700\u7684\u8def\u7531\u53c2\u6570<\/p>\n
The routing middleware parses a route template by splitting it into segments. A segment is typically separated by the \/ character, but it can be any valid character.<\/p>\n
\u8def\u7531\u4e2d\u95f4\u4ef6\u901a\u8fc7\u5c06\u8def\u7531\u6a21\u677f\u62c6\u5206\u4e3a\u6bb5\u6765\u89e3\u6790\u8def\u7531\u6a21\u677f\u3002\u6bb5\u901a\u5e38\u7531\u5b57\u7b26\u5206\u9694\uff0c\u4f46\u5b83\u53ef\u4ee5\u662f\u4efb\u4f55\u6709\u6548\u5b57\u7b26\u3002\/<\/p>\n
DEFINITION<\/b> Segments that use a character other than \/ are called complex segments. I generally recommend that you avoid them and stick to using \/ as a separator. Complex segments have some peculiarities that make them hard to use, so be sure to check the documentation at http:\/\/mng.bz\/D4RE<\/a> before you use them.
\n\u5b9a\u4e49\uff1a \u4f7f\u7528\u5176\u4ed6\u5b57\u7b26\u7684\u7ebf\u6bb5\u79f0\u4e3a\u590d\u6742\u7ebf\u6bb5\u3002\u6211\u901a\u5e38\u5efa\u8bae\u60a8\u907f\u514d\u4f7f\u7528\u5b83\u4eec\u5e76\u575a\u6301\u7528\u4f5c\u5206\u9694\u7b26\u3002\u590d\u6742\u533a\u6bb5\u5177\u6709\u4e00\u4e9b\u7279\u6027\uff0c\u4f7f\u5176\u96be\u4ee5\u4f7f\u7528\uff0c\u56e0\u6b64\u8bf7\u52a1\u5fc5\u5728\u4f7f\u7528 http:\/\/mng.bz\/D4RE<\/a> \u4e4b\u524d\u67e5\u770b\u6587\u6863\u3002<\/p>\nEach segment is either
\n\u6bcf\u4e2a\u6bb5\u662f<\/p>\n
\u2022 A literal value such as product in figure 6.5
\n\u5982\u56fe 6.5 \u6240\u793a\u7684 Literal \u503cproduct<\/p>\n
\u2022 A route parameter such as {category} and {name} in figure 6.5
\n\u8def\u7531\u53c2\u6570\uff0c\u5982\u56fe 6.5 \u4e2d\u7684 \u548c{category}{name}<\/p>\n
The request URL must match literal values exactly (ignoring case). If you need to match a particular URL exactly, you can use a template consisting only of literals.<\/p>\n
\u8bf7\u6c42 URL \u5fc5\u987b\u4e0e\u6587\u5b57\u503c\u5b8c\u5168\u5339\u914d\uff08\u5ffd\u7565\u5927\u5c0f\u5199\uff09\u3002\u5982\u679c\u9700\u8981\u7cbe\u786e\u5339\u914d\u7279\u5b9a URL\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ec5\u5305\u542b\u6587\u672c\u7684\u6a21\u677f\u3002<\/p>\n
TIP<\/b> Literal segments in ASP.NET Core aren\u2019t case-sensitive.
\n\u63d0\u793a\uff1a ASP.NET Core \u4e2d\u7684\u6587\u672c\u6bb5\u4e0d\u533a\u5206\u5927\u5c0f\u5199\u3002<\/p>\n
Imagine that you have a minimal API in your application defined using
\n\u5047\u8bbe\u60a8\u5728\u5e94\u7528\u7a0b\u5e8f\u4e2d\u6709\u4e00\u4e2a\u4f7f\u7528<\/p>\n
\napp.MapGet("\/About\/Contact", () => {\/* *\/})\n<\/pre>\nThis route template, \u201c\/About\/Contact", consists only of literal values, so it matches only the exact URL (ignoring case). None of the following URLs would match this route template:
\n\u6b64\u8def\u7531\u6a21\u677f \u201c\/About\/Contact\u201d \u4ec5\u5305\u542b\u6587\u672c\u503c\uff0c\u56e0\u6b64\u5b83\u4ec5\u5339\u914d\u786e\u5207\u7684 URL\uff08\u5ffd\u7565\u5927\u5c0f\u5199\uff09\u3002\u4ee5\u4e0b URL \u90fd\u4e0d\u5339\u914d\u6b64\u8def\u7531\u6a21\u677f\uff1a<\/p>\n
\u2022 \/about
\n\u2022 \/about-us\/contact
\n\u2022 \/about\/contact\/email
\n\u2022 \/about\/contact-us<\/p>\n
Route parameters are sections of a URL that may vary but are still a match for the template. You define them by giving them a name and placing them in braces, such as {category} or {name}. When used in this way, the parameters are required, so the request URL must have a segment that they correspond to, but the value can vary.<\/p>\n
\u8def\u7531\u53c2\u6570\u662f URL \u7684\u90e8\u5206\uff0c\u8fd9\u4e9b\u90e8\u5206\u53ef\u80fd\u4f1a\u6709\u6240\u4e0d\u540c\uff0c\u4f46\u4ecd\u4e0e\u6a21\u677f\u5339\u914d\u3002\u60a8\u53ef\u4ee5\u901a\u8fc7\u4e3a\u5b83\u4eec\u547d\u540d\u5e76\u5c06\u5b83\u4eec\u653e\u5728\u5927\u62ec\u53f7\u4e2d\u6765\u5b9a\u4e49\u5b83\u4eec\uff0c\u4f8b\u5982{\u7c7b\u522b}\u6216 {name} \u7684\u4ee5\u8fd9\u79cd\u65b9\u5f0f\u4f7f\u7528\u65f6\uff0c\u53c2\u6570\u662f\u5fc5\u9700\u7684\uff0c\u56e0\u6b64\u8bf7\u6c42 URL \u5fc5\u987b\u5177\u6709\u5b83\u4eec\u5bf9\u5e94\u7684\u533a\u6bb5\uff0c\u4f46\u8be5\u503c\u53ef\u80fd\u4f1a\u6709\u6240\u4e0d\u540c\u3002<\/p>\n
The ability to use route parameters gives you great flexibility. The simple route template "\/{category}\/{name}" could be used to match all the product-page URLs in an e-commerce application:
\n\u4f7f\u7528\u8def\u7531\u53c2\u6570\u7684\u80fd\u529b\u4e3a\u60a8\u63d0\u4f9b\u4e86\u6781\u5927\u7684\u7075\u6d3b\u6027\u3002\u7b80\u5355\u7684\u8def\u7531\u6a21\u677f \u201c\/{category}\/{name}\u201d \u53ef\u7528\u4e8e\u5339\u914d\u7535\u5b50\u5546\u52a1\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684\u6240\u6709\u4ea7\u54c1\u9875\u9762 URL\uff1a<\/p>\n
\u2022 \/bags\/rucksack-a\u2014Where category=bags and name=rucksack-a
\n\u2022 \/shoes\/black-size9\u2014Where category=shoes and name=black-size9<\/p>\n
But note that this template would not map the following URLs:
\n\u4f46\u8bf7\u6ce8\u610f\uff0c\u6b64\u6a21\u677f\u4e0d\u4f1a\u6620\u5c04\u4ee5\u4e0b URL\uff1a<\/p>\n
\u2022 \/socks\/\u2014No name parameter specified
\n\u2022 \/trousers\/mens\/formal\u2014Extra URL segment, formal, not found in route template<\/p>\n
When a route template defines a route parameter and the route matches a URL, the value associated with the parameter is captured and stored in a dictionary of values associated with the request. These route values typically drive other behavior in the endpoint and can be injected into the handlers (as you saw briefly in chapter 5) in a process called model binding.<\/p>\n
\u5f53\u8def\u7531\u6a21\u677f\u5b9a\u4e49\u8def\u7531\u53c2\u6570\u5e76\u4e14\u8def\u7531\u4e0e URL \u5339\u914d\u65f6\uff0c\u5c06\u6355\u83b7\u4e0e\u8be5\u53c2\u6570\u5173\u8054\u7684\u503c\u5e76\u5c06\u5176\u5b58\u50a8\u5728\u4e0e\u8bf7\u6c42\u5173\u8054\u7684\u503c\u5b57\u5178\u4e2d\u3002\u8fd9\u4e9b\u8def\u7531\u503c\u901a\u5e38\u9a71\u52a8\u7aef\u70b9\u4e2d\u7684\u5176\u4ed6\u884c\u4e3a\uff0c\u5e76\u4e14\u53ef\u4ee5\u5728\u79f0\u4e3a\u6a21\u578b\u7ed1\u5b9a\u7684\u8fc7\u7a0b\u4e2d\u6ce8\u5165\u5904\u7406\u7a0b\u5e8f\uff08\u5982\u60a8\u5728\u7b2c 5 \u7ae0\u4e2d\u7b80\u8981\u770b\u5230\u7684\u90a3\u6837\uff09\u3002<\/p>\n
DEFINITION<\/b> Route values are the values extracted from a URL based on a given route template. Each route parameter in a template has an associated route value, and the values are stored as a string pair in a dictionary. They can be used during model binding, as you\u2019ll see in chapter 7.
\n\u5b9a\u4e49\uff1a \u8def\u7531\u503c \u662f\u6839\u636e\u7ed9\u5b9a\u8def\u7531\u6a21\u677f\u4ece URL \u4e2d\u63d0\u53d6\u7684\u503c\u3002\u6a21\u677f\u4e2d\u7684\u6bcf\u4e2a\u8def\u7531\u53c2\u6570\u90fd\u6709\u4e00\u4e2a\u5173\u8054\u7684\u8def\u7531\u503c\uff0c\u8fd9\u4e9b\u503c\u4f5c\u4e3a\u5b57\u7b26\u4e32\u5bf9\u5b58\u50a8\u5728\u5b57\u5178\u4e2d\u3002\u5b83\u4eec\u53ef\u4ee5\u5728\u6a21\u578b\u7ed1\u5b9a\u671f\u95f4\u4f7f\u7528\uff0c\u5982\u7b2c 7 \u7ae0\u6240\u793a\u3002<\/p>\n
Literal segments and route parameters are the two cornerstones of ASP.NET Core route templates. With these two concepts, it\u2019s possible to build all manner of URLs for your application. In the remainder of section 6.3 we\u2019ll look at additional features that let you have optional URL segments, provide default values when a segment isn\u2019t specified, and place additional constraints on the values that are valid for a given route parameter.<\/p>\n
\u6587\u5b57\u6bb5\u548c\u8def\u7531\u53c2\u6570\u662f ASP.NET Core \u8def\u7531\u6a21\u677f\u7684\u4e24\u4e2a\u57fa\u77f3\u3002\u6709\u4e86\u8fd9\u4e24\u4e2a\u6982\u5ff5\uff0c\u5c31\u53ef\u4ee5\u4e3a\u60a8\u7684\u5e94\u7528\u7a0b\u5e8f\u6784\u5efa\u5404\u79cd URL\u3002\u5728\u7b2c 6.3 \u8282\u7684\u5176\u4f59\u90e8\u5206\u4e2d\uff0c\u6211\u4eec\u5c06\u4ecb\u7ecd\u5176\u4ed6\u529f\u80fd\uff0c\u8fd9\u4e9b\u529f\u80fd\u5141\u8bb8\u60a8\u4f7f\u7528\u53ef\u9009\u7684 URL \u6bb5\uff0c\u5728\u672a\u6307\u5b9a\u6bb5\u65f6\u63d0\u4f9b\u9ed8\u8ba4\u503c\uff0c\u4ee5\u53ca\u5bf9\u7ed9\u5b9a\u8def\u7531\u53c2\u6570\u6709\u6548\u7684\u503c\u8bbe\u7f6e\u5176\u4ed6\u7ea6\u675f\u3002<\/p>\n
6.3.2 Using optional and default values<\/h3>\n6.3.2 \u4f7f\u7528\u53ef\u9009\u503c\u548c\u9ed8\u8ba4\u503c<\/h3>\n
In section 6.3.1 you saw a simple route template with a literal segment and two required routing parameters. Figure 6.6 shows a more complex route that uses several additional features.<\/p>\n
\u5728 6.3.1 \u8282\u4e2d\uff0c\u60a8\u770b\u5230\u4e86\u4e00\u4e2a\u7b80\u5355\u7684\u8def\u7531\u6a21\u677f\uff0c\u5176\u4e2d\u5305\u542b\u4e00\u4e2a\u6587\u5b57\u6bb5\u548c\u4e24\u4e2a\u5fc5\u9700\u7684\u8def\u7531\u53c2\u6570\u3002\u56fe6.6 \u663e\u793a\u4e86\u4e00\u4e2a\u66f4\u590d\u6742\u7684\u8def\u7531\uff0c\u5b83\u4f7f\u7528\u4e86\u51e0\u4e2a\u9644\u52a0\u529f\u80fd\u3002<\/p>\n
![\"\"](\"\/images\/aspnetcoreinaction\/0606.png\")
<\/p>\n
Figure 6.6 A more complex route template showing literal segments, named route parameters, optional parameters, and default values.
\n\u56fe 6.6 \u4e00\u4e2a\u66f4\u590d\u6742\u7684\u8def\u7531\u6a21\u677f\uff0c\u663e\u793a\u6587\u672c\u6bb5\u3001\u547d\u540d\u8def\u7531\u53c2\u6570\u3001\u53ef\u9009\u53c2\u6570\u548c\u9ed8\u8ba4\u503c\u3002<\/p>\n
The literal product segment and the required {category} parameter are the same as those in in figure 6.6. The {name} parameter looks similar, but it has a default value specified for it by =all. If the URL doesn\u2019t contain a segment corresponding to the {name} parameter, the router will use the all value instead.<\/p>\n
\u6587\u672c product segment \u548c\u6240\u9700\u7684 {category}\u53c2\u6570\u4e0e\u56fe 6.6 \u4e2d\u7684\u76f8\u540c\u3002\u8fd9{name} \u53c2\u6570\u770b\u8d77\u6765\u7c7b\u4f3c\uff0c\u4f46\u5b83\u7684\u9ed8\u8ba4\u503c\u7531 =all \u6307\u5b9a\u3002\u5982\u679c URL \u4e0d\u5305\u542b\u4e0e {name} \u53c2\u6570\u5bf9\u5e94\u7684\u6bb5\uff0c\u5219\u8def\u7531\u5668\u5c06\u6539\u7528 all \u503c\u3002<\/p>\n
The final segment of figure 6.6, {id?}, defines an optional route parameter called id. This segment of the URL is optional. If this segment is present, the router captures the value for the {id} parameter; if the segment isn\u2019t there, the router doesn\u2019t create a route value for id.<\/p>\n
\u56fe 6.6 \u7684\u6700\u540e\u4e00\u6bb5 {id\uff1f} \u5b9a\u4e49\u4e86\u4e00\u4e2a\u540d\u4e3a id \u7684\u53ef\u9009\u8def\u7531\u53c2\u6570\u3002URL \u7684\u6b64\u6bb5\u662f\u53ef\u9009\u7684\u3002\u5982\u679c\u5b58\u5728\u6b64\u6bb5\uff0c\u5219\u8def\u7531\u5668\u5c06\u6355\u83b7 {id} \u53c2\u6570\u7684\u503c;\u5982\u679c segment \u4e0d\u5b58\u5728\uff0c\u5219\u8def\u7531\u5668\u4e0d\u4f1a\u4e3a id \u521b\u5efa route \u503c\u3002<\/p>\n
You can specify any number of route parameters in your templates, and these values will be available to you for model binding. The complex route template shown in figure 6.6 allows you to match a greater variety of URLs by making {name} and {id} optional and by providing a default for {name}. Table 6.1 shows some of the URLs that this template would match and the corresponding route values that the router would set.<\/p>\n
\u60a8\u53ef\u4ee5\u5728\u6a21\u677f\u4e2d\u6307\u5b9a\u4efb\u610f\u6570\u91cf\u7684\u8def\u7531\u53c2\u6570\uff0c\u8fd9\u4e9b\u503c\u5c06\u53ef\u7528\u4e8e\u6a21\u578b\u7ed1\u5b9a\u3002\u56fe\u4e2d\u6240\u793a\u7684\u590d\u6742\u8def\u7531\u6a21\u677f6.6 \u5141\u8bb8\u60a8\u901a\u8fc7\u4ee5\u4e0b\u65b9\u5f0f\u5339\u914d\u66f4\u591a\u79cd\u7c7b\u7684 URL{\u59d3\u540d}\u548c {id} \u53ef\u9009\uff0c\u5e76\u901a\u8fc7\u4e3a{\u59d3\u540d}\u3002\u8868 6.1 \u663e\u793a\u4e86\u6b64\u6a21\u677f\u5c06\u5339\u914d\u7684\u4e00\u4e9b URL \u4ee5\u53ca\u8def\u7531\u5668\u5c06\u8bbe\u7f6e\u7684\u76f8\u5e94\u8def\u7531\u503c\u3002<\/p>\n
Table 6.1 URLs that would match the template of figure 6.7 and their corresponding route values
\n\u8868 6.1 \u4e0e\u56fe 6.7 \u4e2d\u7684\u6a21\u677f\u5339\u914d\u7684 URL \u53ca\u5176\u76f8\u5e94\u7684\u8def\u7531\u503c<\/p>\n
\n\u5c06 URL \u6620\u5c04\u5230\u7aef\u70b9\u5904\u7406\u7a0b\u5e8f<\/li>\n
\n\u4f7f\u7528\u7ea6\u675f\u548c\u9ed8\u8ba4\u503c\u6765\u5339\u914d URL<\/li>\n
\n\u4ece\u8def\u7531\u53c2\u6570\u751f\u6210 URL<\/li>\n<\/ul>\n
In chapter 5 you learned how to define minimal APIs, how to return responses, and how to work with filters and route groups. One crucial aspect of minimal APIs that we touched on only lightly is how ASP.NET Core selects a specific endpoint from all the handlers defined, based on the incoming request URL. This process, called routing, is the focus of this chapter.<\/p>\n
\u5728\u7b2c 5 \u7ae0\u4e2d\uff0c\u60a8\u5b66\u4e60\u4e86\u5982\u4f55\u5b9a\u4e49\u6700\u5c0f API\u3001\u5982\u4f55\u8fd4\u56de\u54cd\u5e94\u4ee5\u53ca\u5982\u4f55\u4f7f\u7528\u7b5b\u9009\u6761\u4ef6\u548c\u8def\u7531\u7ec4\u3002\u6211\u4eec\u4ec5\u7565\u5fae\u6d89\u53ca\u7684\u6700\u5c0f API \u7684\u4e00\u4e2a\u5173\u952e\u65b9\u9762\u662f ASP.NET Core \u5982\u4f55\u6839\u636e\u4f20\u5165\u8bf7\u6c42 URL \u4ece\u5b9a\u4e49\u7684\u6240\u6709\u5904\u7406\u7a0b\u5e8f\u4e2d\u9009\u62e9\u7279\u5b9a\u7aef\u70b9\u3002\u6b64\u8fc7\u7a0b\u79f0\u4e3a routing\uff0c\u662f\u672c\u7ae0\u7684\u91cd\u70b9\u3002<\/p>\n
This chapter begins by identifying the need for routing and why it\u2019s useful. You\u2019ll learn about the endpoint routing system introduced in ASP.NET Core 3.0 and why it was introduced, and explore the flexibility routing can bring to the URLs you expose.<\/p>\n
\u672c\u7ae0\u9996\u5148\u786e\u5b9a routing \u7684\u9700\u6c42\u4ee5\u53ca\u5b83\u4e3a\u4ec0\u4e48\u6709\u7528\u3002\u60a8\u5c06\u4e86\u89e3 ASP.NET Core 3.0 \u4e2d\u5f15\u5165\u7684\u7aef\u70b9\u8def\u7531\u7cfb\u7edf\u53ca\u5176\u5f15\u5165\u539f\u56e0\uff0c\u5e76\u63a2\u7d22\u8def\u7531\u53ef\u4ee5\u4e3a\u60a8\u516c\u5f00\u7684 URL \u5e26\u6765\u7684\u7075\u6d3b\u6027\u3002<\/p>\n
The bulk of this chapter focuses on the route template syntax and how it can be used with minimal APIs. You\u2019ll learn about features such as optional parameters, default parameters, and constraints, as well as how to extract values from the URL automatically. Although we\u2019re focusing on minimal APIs in this chapter, the same routing system is used with Razor Pages and Model-View-Controller (MVC), as you\u2019ll see in chapter 14.<\/p>\n
\u672c\u7ae0\u7684\u5927\u90e8\u5206\u5185\u5bb9\u91cd\u70b9\u4ecb\u7ecd\u8def\u7531\u6a21\u677f\u8bed\u6cd5\u4ee5\u53ca\u5982\u4f55\u5c06\u5176\u4e0e\u6700\u5c11\u7684 API \u4e00\u8d77\u4f7f\u7528\u3002\u60a8\u5c06\u4e86\u89e3\u53ef\u9009\u53c2\u6570\u3001\u9ed8\u8ba4\u53c2\u6570\u548c\u7ea6\u675f\u7b49\u529f\u80fd\uff0c\u4ee5\u53ca\u5982\u4f55\u81ea\u52a8\u4ece URL \u4e2d\u63d0\u53d6\u503c\u3002\u5c3d\u7ba1\u6211\u4eec\u5728\u672c\u7ae0\u4e2d\u91cd\u70b9\u4ecb\u7ecd\u4e86\u6700\u5c11\u7684 API\uff0c\u4f46 Razor Pages \u548c\u6a21\u578b\u89c6\u56fe\u63a7\u5236\u5668 \uff08MVC\uff09 \u4f7f\u7528\u76f8\u540c\u7684\u8def\u7531\u7cfb\u7edf\uff0c\u5982\u7b2c 14 \u7ae0\u6240\u793a\u3002<\/p>\n
In section 6.4 I describe how to use the routing system to generate URLs, which you can use to create links and redirect requests for your application. One benefit of using a routing system is that it decouples your handlers from the underlying URLs they\u2019re associated with. You can use URL generation to avoid littering your code with hardcoded URLs like \/product\/view\/3. Instead, you can generate the URLs at runtime, based on the routing system. This approach makes changing the URL for a given endpoint easier: instead of your having to hunt down every place where you used the endpoint\u2019s URL, the URLs are updated for you automatically, with no other changes required.<\/p>\n
\u5728 6.4 \u8282\u4e2d\uff0c\u6211\u5c06\u4ecb\u7ecd\u5982\u4f55\u4f7f\u7528\u8def\u7531\u7cfb\u7edf\u751f\u6210 URL\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u8fd9\u4e9b URL \u4e3a\u60a8\u7684\u5e94\u7528\u7a0b\u5e8f\u521b\u5efa\u94fe\u63a5\u548c\u91cd\u5b9a\u5411\u8bf7\u6c42\u3002\u4f7f\u7528\u8def\u7531\u7cfb\u7edf\u7684\u4e00\u4e2a\u597d\u5904\u662f\uff0c\u5b83\u5c06\u5904\u7406\u7a0b\u5e8f\u4e0e\u5b83\u4eec\u5173\u8054\u7684\u5e95\u5c42 URL \u5206\u79bb\u3002\u60a8\u53ef\u4ee5\u4f7f\u7528 URL \u751f\u6210\u6765\u907f\u514d\u5c06\u4ee3\u7801\u4e0e\u786c\u7f16\u7801\u7684 URL \uff08\u5982 \/product\/view\/3\uff09\u6df7\u5728\u4e00\u8d77\u3002\u76f8\u53cd\uff0c\u60a8\u53ef\u4ee5\u5728\u8fd0\u884c\u65f6\u6839\u636e\u8def\u7531\u7cfb\u7edf\u751f\u6210 URL\u3002\u8fd9\u79cd\u65b9\u6cd5\u4f7f\u66f4\u6539\u7ed9\u5b9a\u7ec8\u7aef\u8282\u70b9\u7684 URL \u53d8\u5f97\u66f4\u52a0\u5bb9\u6613\uff1a\u60a8\u4e0d\u5fc5\u5bfb\u627e\u4f7f\u7528\u7ec8\u7aef\u8282\u70b9 URL \u7684\u6bcf\u4e2a\u4f4d\u7f6e\uff0cURL \u4f1a\u81ea\u52a8\u4e3a\u60a8\u66f4\u65b0\uff0c\u65e0\u9700\u8fdb\u884c\u5176\u4ed6\u66f4\u6539\u3002<\/p>\n
By the end of this chapter, you should have a much clearer understanding of how an ASP.NET Core application works. You can think of routing as being the glue that ties the middleware pipeline to endpoints. With middleware, endpoints, and routing under your belt, you\u2019ll be writing web apps in no time!<\/p>\n
\u5728\u672c\u7ae0\u7ed3\u675f\u65f6\uff0c\u60a8\u5e94\u8be5\u5bf9 ASP.NET Core \u5e94\u7528\u7a0b\u5e8f\u7684\u5de5\u4f5c\u539f\u7406\u6709\u4e86\u66f4\u6e05\u6670\u7684\u4e86\u89e3\u3002\u60a8\u53ef\u4ee5\u5c06\u8def\u7531\u89c6\u4e3a\u5c06\u4e2d\u95f4\u4ef6\u7ba1\u9053\u4e0e\u7ec8\u7aef\u8282\u70b9\u8054\u7cfb\u8d77\u6765\u7684\u7c98\u5408\u5242\u3002\u6709\u4e86\u4e2d\u95f4\u4ef6\u3001\u7ec8\u7aef\u8282\u70b9\u548c\u8def\u7531\uff0c\u60a8\u5c06\u7acb\u5373\u7f16\u5199 Web \u5e94\u7528\u7a0b\u5e8f\uff01<\/p>\n
6.1 What is routing?<\/h2>\n6.1 \u4ec0\u4e48\u662f\u8def\u7531\uff1f<\/h2>\n
Routing is the process of mapping an incoming request to a method that will handle it. You can use routing to control the URLs you expose in your application. You can also use routing to enable powerful features such as mapping multiple URLs to the same handler and automatically extracting data from a request\u2019s URL.<\/p>\n
\u8def\u7531\u662f\u5c06\u4f20\u5165\u8bf7\u6c42\u6620\u5c04\u5230\u5c06\u5904\u7406\u8be5\u8bf7\u6c42\u7684\u65b9\u6cd5\u7684\u8fc7\u7a0b\u3002\u60a8\u53ef\u4ee5\u4f7f\u7528\u8def\u7531\u6765\u63a7\u5236\u5728\u5e94\u7528\u7a0b\u5e8f\u4e2d\u516c\u5f00\u7684 URL\u3002\u60a8\u8fd8\u53ef\u4ee5\u4f7f\u7528\u8def\u7531\u6765\u542f\u7528\u5f3a\u5927\u7684\u529f\u80fd\uff0c\u4f8b\u5982\u6620\u5c04\u591a\u4e2a URL \u6307\u5411\u540c\u4e00\u5904\u7406\u7a0b\u5e8f\uff0c\u5e76\u81ea\u52a8\u4ece\u8bf7\u6c42\u7684 URL \u4e2d\u63d0\u53d6\u6570\u636e\u3002<\/p>\n
In chapter 4 you saw that an ASP.NET Core application contains a middleware pipeline, which defines the behavior of your application. Middleware is well suited to handling both cross-cutting concerns, such as logging and error handling, and narrowly focused requests, such as requests for images and CSS files.<\/p>\n
\u5728\u7b2c 4 \u7ae0\u4e2d\uff0c\u60a8\u770b\u5230 ASP.NET Core \u5e94\u7528\u7a0b\u5e8f\u5305\u542b\u4e00\u4e2a\u4e2d\u95f4\u4ef6\u7ba1\u9053\uff0c\u5b83\u5b9a\u4e49\u4e86\u5e94\u7528\u7a0b\u5e8f\u7684\u884c\u4e3a\u3002\u4e2d\u95f4\u4ef6\u975e\u5e38\u9002\u5408\u5904\u7406\u6a2a\u5207\u5173\u6ce8\u70b9\uff08\u5982\u65e5\u5fd7\u8bb0\u5f55\u548c\u9519\u8bef\u5904\u7406\uff09\u548c\u8303\u56f4\u72ed\u7a84\u7684\u8bf7\u6c42\uff08\u5982\u56fe\u50cf\u548c CSS \u6587\u4ef6\u8bf7\u6c42\uff09\u3002<\/p>\n
To handle more complex application logic, you\u2019ll typically use the EndpointMiddleware at the end of your middleware pipeline. This middleware can handle an appropriate request by invoking a method known as a handler and using the result to generate a response. Previous chapters described using minimal API endpoint handlers, but there are other types of handlers, such as MVC Action methods and Razor Pages, as you\u2019ll learn in part 2 of this book.<\/p>\n
\u4e3a\u4e86\u5904\u7406\u66f4\u590d\u6742\u7684\u5e94\u7528\u7a0b\u5e8f\u903b\u8f91\uff0c\u60a8\u901a\u5e38\u4f1a\u5728\u4e2d\u95f4\u4ef6\u7ba1\u9053\u7684\u672b\u5c3e\u4f7f\u7528 EndpointMiddleware\u3002\u6b64\u4e2d\u95f4\u4ef6\u53ef\u4ee5\u901a\u8fc7\u8c03\u7528\u79f0\u4e3a\u5904\u7406\u7a0b\u5e8f\u7684\u65b9\u6cd5\u5e76\u4f7f\u7528\u7ed3\u679c\u751f\u6210\u54cd\u5e94\u6765\u5904\u7406\u9002\u5f53\u7684\u8bf7\u6c42\u3002\u524d\u9762\u7684\u7ae0\u8282\u4ecb\u7ecd\u4e86\u4f7f\u7528\u6700\u5c11\u7684 API \u7aef\u70b9\u5904\u7406\u7a0b\u5e8f\uff0c\u4f46\u8fd8\u6709\u5176\u4ed6\u7c7b\u578b\u7684\u5904\u7406\u7a0b\u5e8f\uff0c\u4f8b\u5982 MVC\u4f5c\u65b9\u6cd5\u548c Razor Pages\uff0c\u60a8\u5c06\u5728\u672c\u4e66\u7684\u7b2c 2 \u90e8\u5206\u4e2d\u5b66\u4e60\u3002<\/p>\n
One aspect that I\u2019ve glossed over so far is how the EndpointMiddleware selects which handler executes when you receive a request. What makes a request appropriate for a given handler? The process of mapping a request to a handler is routing.<\/p>\n
\u5230\u76ee\u524d\u4e3a\u6b62\uff0c\u6211\u6240\u8ba8\u8bba\u7684\u4e00\u4e2a\u65b9\u9762\u662f EndpointMiddleware \u5982\u4f55\u9009\u62e9\u5728\u60a8\u6536\u5230\u8bf7\u6c42\u65f6\u6267\u884c\u54ea\u4e2a\u5904\u7406\u7a0b\u5e8f\u3002\u4ec0\u4e48\u4f7f\u8bf7\u6c42\u9002\u5408\u7ed9\u5b9a\u7684\u5904\u7406\u7a0b\u5e8f\uff1f\u5c06\u8bf7\u6c42\u6620\u5c04\u5230\u5904\u7406\u7a0b\u5e8f\u7684\u8fc7\u7a0b\u662f\u8def\u7531\u3002<\/p>\n
Definition<\/strong> Routing in ASP.NET Core is the process of selecting a specific handler for an incoming HTTP request. In minimal APIs, the handler is the endpoint handler associated with a route. In Razor Pages, the handler is a page handler method defined in a Razor Page. In MVC, the handler is an action method in a controller. In chapters 3 to 5, you saw several simple applications built with minimal APIs. In chapter 5, you learned the basics of routing for minimal APIs, but it\u2019s worth exploring why routing is useful as well as how to use it. Even a simple URL path such as \/person uses routing to determine which handler should be executed, as shown in figure 6.1.<\/p>\n \u5728\u7b2c 3 \u7ae0\u5230\u7b2c 5 \u7ae0\u4e2d\uff0c\u60a8\u770b\u5230\u4e86\u51e0\u4e2a\u4f7f\u7528\u6700\u5c11 API \u6784\u5efa\u7684\u7b80\u5355\u5e94\u7528\u7a0b\u5e8f\u3002\u5728\u7b2c 5 \u7ae0\u4e2d\uff0c\u60a8\u5b66\u4e60\u4e86\u6700\u5c0f API \u7684\u8def\u7531\u57fa\u7840\u77e5\u8bc6\uff0c\u4f46\u503c\u5f97\u63a2\u7d22\u4e3a\u4ec0\u4e48\u8def\u7531\u5f88\u6709\u7528\u4ee5\u53ca\u5982\u4f55\u4f7f\u7528\u5b83\u3002\u5373\u4f7f\u662f\u7b80\u5355\u7684 URL \u8def\u5f84\uff0c\u5982 \/person\uff0c\u4e5f\u4f7f\u7528\u8def\u7531\u6765\u786e\u5b9a\u5e94\u8be5\u6267\u884c\u54ea\u4e2a\u5904\u7406\u7a0b\u5e8f\uff0c\u5982\u56fe 6.1 \u6240\u793a\u3002<\/p>\n Figure 6.1 The router compares the request URL with a list of configured route templates to determine which handler to execute. On the face of it, that seems pretty simple. You may wonder why I need a whole chapter to explain that obvious mapping. The simplicity of the mapping in this case belies how powerful routing can be. If this approach, using a direct comparison with static strings, were the only one available, you\u2019d be severely limited in the applications you could feasibly build.<\/p>\n \u4ece\u8868\u9762\u4e0a\u770b\uff0c\u8fd9\u4f3c\u4e4e\u5f88\u7b80\u5355\u3002\u4f60\u53ef\u80fd\u4f1a\u60f3\u4e3a\u4ec0\u4e48\u6211\u9700\u8981\u4e00\u6574\u7ae0\u6765\u89e3\u91ca\u8fd9\u4e2a\u660e\u663e\u7684\u6620\u5c04\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u6620\u5c04\u7684\u7b80\u5355\u6027\u63a9\u76d6\u4e86\u8def\u7531\u7684\u5f3a\u5927\u529f\u80fd\u3002\u5982\u679c\u8fd9\u79cd\u65b9\u6cd5\uff08\u4f7f\u7528\u4e0e\u9759\u6001\u5b57\u7b26\u4e32\u7684\u76f4\u63a5\u6bd4\u8f83\uff09\u662f\u552f\u4e00\u53ef\u7528\u7684\u65b9\u6cd5\uff0c\u90a3\u4e48\u60a8\u53ef\u4ee5\u6784\u5efa\u7684\u5e94\u7528\u7a0b\u5e8f\u5c06\u53d7\u5230\u4e25\u91cd\u9650\u5236\u3002<\/p>\n Consider an e-commerce application that sells multiple products. Each product needs to have its own URL, so if you were using a purely static routing system, you\u2019d have only two options:<\/p>\n \u8003\u8651\u4e00\u4e2a\u9500\u552e\u591a\u79cd\u4ea7\u54c1\u7684\u7535\u5b50\u5546\u52a1\u5e94\u7528\u7a0b\u5e8f\u3002\u6bcf\u4e2a\u4ea7\u54c1\u90fd\u9700\u8981\u6709\u81ea\u5df1\u7684 URL\uff0c\u56e0\u6b64\u5982\u679c\u60a8\u4f7f\u7528\u7684\u662f\u7eaf\u9759\u6001\u8def\u7531\u7cfb\u7edf\uff0c\u5219\u53ea\u6709\u4e24\u4e2a\u9009\u9879\uff1a<\/p>\n Use a different handler for every product in your product range. That approach would be unfeasible for almost any realistically sized product range. Use a single handler, and use the query string to differentiate among products. This approach is much more practical, but you\u2019d end up with somewhat-ugly URLs, such as "\/product?name=big-widget" or "\/product?id=12". Definition<\/strong> The query string is part of a URL containing additional data that doesn\u2019t fit in the path. It isn\u2019t used by the routing infrastructure to identify which handler to execute, but ASP.NET Core can extract values from the query string automatically in a process called model binding, as you\u2019ll see in chapter 7. The query string in the preceding example is id=12. With routing, you can have a single endpoint handler that can handle multiple URLs without having to resort to ugly query strings. From the point of the view of the endpoint handler, the query string and routing approaches are similar; the handler returns the results for the correct product dynamically as appropriate. The difference is that with routing, you can completely customize the URLs, as shown in figure 6.2. This feature gives you much more flexibility and can be important in real-life applications for search engine optimization (SEO).<\/p>\n \u901a\u8fc7\u8def\u7531\uff0c\u60a8\u53ef\u4ee5\u62e5\u6709\u4e00\u4e2a\u53ef\u4ee5\u5904\u7406\u591a\u4e2a URL \u7684\u7ec8\u7aef\u8282\u70b9\u5904\u7406\u7a0b\u5e8f\uff0c\u800c\u4e0d\u5fc5\u6c42\u52a9\u4e8e\u96be\u61c2\u7684\u67e5\u8be2\u5b57\u7b26\u4e32\u3002\u4ece\u7aef\u70b9\u7684\u89c6\u89d2handler\uff0c\u5219\u67e5\u8be2\u5b57\u7b26\u4e32\u548c\u8def\u7531\u65b9\u6cd5\u7c7b\u4f3c;\u5904\u7406\u7a0b\u5e8f\u4f1a\u6839\u636e\u9700\u8981\u52a8\u6001\u8fd4\u56de\u6b63\u786e\u4ea7\u54c1\u7684\u7ed3\u679c\u3002\u533a\u522b\u5728\u4e8e\uff0c\u4f7f\u7528\u8def\u7531\uff0c\u60a8\u53ef\u4ee5\u5b8c\u5168\u81ea\u5b9a\u4e49 URL\uff0c\u5982\u56fe 6.2 \u6240\u793a\u3002\u6b64\u529f\u80fd\u4e3a\u60a8\u63d0\u4f9b\u4e86\u66f4\u5927\u7684\u7075\u6d3b\u6027\uff0c\u5e76\u4e14\u5728\u641c\u7d22\u5f15\u64ce\u4f18\u5316 \uff08SEO\uff09 \u7684\u5b9e\u9645\u5e94\u7528\u7a0b\u5e8f\u4e2d\u53ef\u80fd\u5f88\u91cd\u8981\u3002<\/p>\n Note<\/strong> With the flexibility of routing, you can encode the hierarchy of your site properly in your URLs, as described in Google\u2019s SEO starter guide at http:\/\/mng.bz\/EQ2J<\/a>. Figure 6.2 If you use static URL-based mapping, you need a different handler for every product in your product range. With a query string, you can use a single handler, and the query string contains the data. With routing, multiple URLs map to a single handler, and a dynamic parameter captures the difference in the URL. As well as enabling dynamic URLs, routing fundamentally decouples the URLs in your application from the definition of your handlers.<\/p>\n \u9664\u4e86\u542f\u7528\u52a8\u6001 URL \u4e4b\u5916\uff0c\u8def\u7531\u8fd8\u4ece\u6839\u672c\u4e0a\u5c06\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684 URL \u4e0e\u5904\u7406\u7a0b\u5e8f\u7684\u5b9a\u4e49\u5206\u79bb\u3002<\/p>\n File-system based routing With routing it\u2019s easy to modify your exposed URLs without changing any filenames or locations. You can also use routing to create friendlier URLs for users, which can improve discovery and \u201chackability.\u201d All of the following routes could point to the same handler:<\/p>\n \u901a\u8fc7\u8def\u7531\uff0c\u53ef\u4ee5\u8f7b\u677e\u4fee\u6539\u516c\u5f00\u7684 URL\uff0c\u800c\u65e0\u9700\u66f4\u6539\u4efb\u4f55\u6587\u4ef6\u540d\u6216\u4f4d\u7f6e\u3002\u60a8\u8fd8\u53ef\u4ee5\u4f7f\u7528\u8def\u7531\u4e3a\u7528\u6237\u521b\u5efa\u66f4\u53cb\u597d\u7684 URL\uff0c\u8fd9\u53ef\u4ee5\u63d0\u9ad8\u53d1\u73b0\u548c\u201c\u53ef\u9ed1\u5ba2\u653b\u51fb\u6027\u201d\u3002\u4ee5\u4e0b\u6240\u6709\u8def\u7531\u90fd\u53ef\u4ee5\u6307\u5411\u540c\u4e00\u4e2a\u5904\u7406\u7a0b\u5e8f\uff1a<\/p>\n This level of customization isn\u2019t often necessary, but it\u2019s quite useful to have the capability to customize your app\u2019s URLs when you need it. In the next section we\u2019ll look at how routing works in practice in ASP.NET Core.<\/p>\n \u8fd9\u79cd\u7ea7\u522b\u7684\u81ea\u5b9a\u4e49\u901a\u5e38\u4e0d\u662f\u5fc5\u9700\u7684\uff0c\u4f46\u80fd\u591f\u5728\u9700\u8981\u65f6\u81ea\u5b9a\u4e49\u5e94\u7528\u7a0b\u5e8f\u7684 URL \u975e\u5e38\u6709\u7528\u3002\u5728\u4e0b\u4e00\u8282\u4e2d\uff0c\u6211\u4eec\u5c06\u4e86\u89e3 ASP.NET Core \u4e2d\u7684\u8def\u7531\u5b9e\u9645\u5de5\u4f5c\u539f\u7406\u3002<\/p>\n In this section I describe how endpoint routing works in ASP.NET Core, specifically with respect to minimal APIs and the middleware pipeline. In chapter 14 you\u2019ll learn how routing is used with Razor Pages and the ASP.NET Core MVC framework.<\/p>\n \u5728\u672c\u8282\u4e2d\uff0c\u6211\u5c06\u4ecb\u7ecd\u7ec8\u7aef\u8282\u70b9\u8def\u7531\u5728 ASP.NET Core \u4e2d\u7684\u5de5\u4f5c\u539f\u7406\uff0c\u7279\u522b\u662f\u5173\u4e8e\u6700\u5c0f API \u548c\u4e2d\u95f4\u4ef6\u7ba1\u9053\u3002\u5728\u7b2c 14 \u7ae0\u4e2d\uff0c\u60a8\u5c06\u4e86\u89e3\u5982\u4f55\u5c06\u8def\u7531\u4e0e Razor Pages \u548c ASP.NET Core MVC \u6846\u67b6\u4e00\u8d77\u4f7f\u7528\u3002<\/p>\n Routing has been part of ASP.NET Core since its inception, but it has been through some big changes. In ASP.NET Core 2.0 and 2.1, routing was restricted to Razor Pages and the ASP.NET Core MVC framework. There was no dedicated routing middleware in the middleware pipeline; routing happened only within Razor Pages or MVC components.<\/p>\n \u8def\u7531\u81ea\u6210\u7acb\u4ee5\u6765\u4e00\u76f4\u662f ASP.NET Core \u7684\u4e00\u90e8\u5206\uff0c\u4f46\u5b83\u7ecf\u5386\u4e86\u4e00\u4e9b\u91cd\u5927\u53d8\u5316\u3002\u5728 ASP.NET Core \u4e2d2.0 \u548c 2.1 \u4e2d\uff0c\u8def\u7531\u4ec5\u9650\u4e8e Razor Pages \u548c ASP.NET Core MVC \u6846\u67b6\u3002\u4e2d\u95f4\u4ef6\u7ba1\u9053\u4e2d\u6ca1\u6709\u4e13\u7528\u7684\u8def\u7531\u4e2d\u95f4\u4ef6;\u8def\u7531\u4ec5\u5728 Razor Pages \u6216 MVC \u7ec4\u4ef6\u4e2d\u53d1\u751f\u3002<\/p>\n Unfortunately, restricting routing to the MVC and Razor Pages infrastructure made some things a bit messy. Some cross-cutting concerns, such as authorization, were restricted to the MVC infrastructure and were hard to use from other middleware in your application. That restriction caused inevitable duplication, which wasn\u2019t ideal.<\/p>\n \u9057\u61be\u7684\u662f\uff0c\u5c06\u8def\u7531\u5230 MVC \u548c Razor Pages \u57fa\u7840\u7ed3\u6784\u4f1a\u4f7f\u67d0\u4e9b\u4e8b\u60c5\u53d8\u5f97\u6709\u70b9\u6df7\u4e71\u3002\u4e00\u4e9b\u6a2a\u5207\u5173\u6ce8\u70b9\uff08\u5982\u6388\u6743\uff09\u4ec5\u9650\u4e8e MVC \u57fa\u7840\u8bbe\u65bd\uff0c\u5e76\u4e14\u5f88\u96be\u4ece\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684\u5176\u4ed6\u4e2d\u95f4\u4ef6\u4e2d\u4f7f\u7528\u3002\u8fd9\u79cd\u9650\u5236\u5bfc\u81f4\u4e86\u4e0d\u53ef\u907f\u514d\u7684\u91cd\u590d\uff0c\u8fd9\u5e76\u4e0d\u7406\u60f3\u3002<\/p>\n ASP.NET Core 3.0 introduced a new routing system: endpoint routing. Endpoint routing makes the routing system a more fundamental feature of ASP.NET Core and no longer ties it to the MVC infrastructure. Now Razor Pages, MVC, and other middleware can all use the same routing system. .NET 7 continues to use the same endpoint routing system, which is integral to the minimal API functionality that was introduced in .NET 6.<\/p>\n ASP.NET Core 3.0 \u5f15\u5165\u4e86\u4e00\u4e2a\u65b0\u7684\u8def\u7531\u7cfb\u7edf\uff1a\u7aef\u70b9\u8def\u7531\u3002\u7aef\u70b9\u8def\u7531\u4f7f\u8def\u7531\u7cfb\u7edf\u6210\u4e3a ASP.NET Core \u7684\u66f4\u57fa\u672c\u529f\u80fd\uff0c\u4e0d\u518d\u5c06\u5176\u7ed1\u5b9a\u5230 MVC \u57fa\u7840\u8bbe\u65bd\u3002\u73b0\u5728\uff0cRazor Pages\u3001MVC \u548c\u5176\u4ed6\u4e2d\u95f4\u4ef6\u90fd\u53ef\u4ee5\u4f7f\u7528\u76f8\u540c\u7684\u8def\u7531\u7cfb\u7edf\u3002.NET 7 \u7ee7\u7eed\u4f7f\u7528\u76f8\u540c\u7684\u7ec8\u7ed3\u70b9\u8def\u7531\u7cfb\u7edf\uff0c\u8fd9\u662f .NET 6 \u4e2d\u5f15\u5165\u7684\u6700\u5c0f API \u529f\u80fd\u4e0d\u53ef\u6216\u7f3a\u7684\u4e00\u90e8\u5206\u3002<\/p>\n Endpoint routing is fundamental to all but the simplest ASP.NET Core apps. It\u2019s implemented with two pieces of middleware, which you\u2019ve already seen:<\/p>\n \u7aef\u70b9\u8def\u7531\u662f\u9664\u6700\u7b80\u5355\u7684 ASP.NET Core \u5e94\u7528\u7a0b\u5e8f\u4e4b\u5916\u7684\u6240\u6709\u5e94\u7528\u7a0b\u5e8f\u7684\u57fa\u7840\u3002\u5b83\u662f\u901a\u8fc7\u4e24\u4e2a\u4e2d\u95f4\u4ef6\u5b9e\u73b0\u7684\uff0c\u60a8\u5df2\u7ecf\u770b\u5230\u4e86\uff1a<\/p>\n EndpointRoutingMiddleware\u2014This middleware chooses which registered endpoints execute for a given request at runtime. To make it easier to distinguish between the two types of middleware, I\u2019ll be referring to this middleware as the RoutingMiddleware throughout this book. EndpointMiddleware\u2014This middleware is typically placed at the end of your middleware pipeline. The middleware executes the endpoint selected by the RoutingMiddleware at runtime. You register the endpoints in your application by calling Map* functions on an IEndpointRouteBuilder instance. In .NET 7 apps, this instance typically is a WebApplication instance but doesn\u2019t have to be, as you\u2019ll see in chapter 30.<\/p>\n \u60a8\u53ef\u4ee5\u901a\u8fc7\u5728 IEndpointRouteBuilder \u5b9e\u4f8b\u4e0a\u8c03\u7528 Map* \u51fd\u6570\u5728\u5e94\u7528\u7a0b\u5e8f\u4e2d\u6ce8\u518c\u7ec8\u7aef\u8282\u70b9\u3002\u5728 .NET 7 \u5e94\u7528\u7a0b\u5e8f\u4e2d\uff0c\u6b64\u5b9e\u4f8b\u901a\u5e38\u662f Web- Application \u5b9e\u4f8b\uff0c\u4f46\u5e76\u975e\u5fc5\u987b\u5982\u6b64\uff0c\u5982\u7b2c 30 \u7ae0\u6240\u793a\u3002<\/p>\n Definition<\/em> An endpoint in ASP.NET Core is a handler that returns a response. Each endpoint is associated with a URL pattern. Depending on the type of application you\u2019re building, minimal API handlers, Razor Page handlers, or MVC controller action methods typically make up the bulk of the endpoints in an application. You can also use simple middleware as an endpoint or a health-check endpoint, for example. WebApplication implements IEndpointRouteBuilder, so you can register endpoints on it directly. Listing 6.1 shows how you\u2019d register several endpoints:<\/p>\n WebApplication \u5b9e\u73b0 IEndpointRouteBuilder\uff0c\u56e0\u6b64\u60a8\u53ef\u4ee5\u76f4\u63a5\u5728\u5176\u4e0a\u6ce8\u518c\u7aef\u70b9\u3002\u6e05\u5355 6.1 \u5c55\u793a\u4e86\u5982\u4f55\u6ce8\u518c\u591a\u4e2a\u7aef\u70b9\uff1a<\/p>\n A minimal API handler using MapGet(), as you\u2019ve seen in previous chapters. A health-check endpoint using MapHealthChecks(). You can read more about health checks at http:\/\/mng.bz\/N2YD<\/a>. All Razor Pages endpoints in the application using MapRazorPages(). You\u2019ll learn more about routing with Razor Pages in chapter 14. Listing 6.1 Registering multiple endpoints with WebApplication \u2776 Adds the services required by the health-check middleware and Razor Pages \u2777 Registers a minimal API endpoint that returns \u201cHello World!\u201d at the route \/test \u2778 Registers a health-check endpoint at the route \/healthz \u2779 Registers all the Razor Pages in your application as endpoints Each endpoint is associated with a route template that defines which URLs the endpoint should match. You can see two route templates, "\/healthz" and "\/test", in listing 6.1.<\/p>\n \u6bcf\u4e2a\u7ec8\u7aef\u8282\u70b9\u90fd\u4e0e\u4e00\u4e2a\u8def\u7531\u6a21\u677f\u76f8\u5173\u8054\uff0c\u8be5\u6a21\u677f\u5b9a\u4e49\u7ec8\u7aef\u8282\u70b9\u5e94\u5339\u914d\u7684 URL\u3002\u5728\u6e05\u5355 6.1 \u4e2d\u53ef\u4ee5\u770b\u5230\u4e24\u4e2a\u8def\u7531\u6a21\u677f\uff0c\u201c\/healthz\u201d \u548c \u201c\/test\u201d\u3002<\/p>\n DEFINITION<\/b> A route template is a URL pattern that is used to match against request URLs, which are strings of fixed values, such as "\/test" in the previous listing. They can also contain placeholders for variables, as you\u2019ll see in section 6.3. The WebApplication stores the registered routes and endpoints in a dictionary that\u2019s shared by the RoutingMiddleware and the EndpointMiddleware.<\/p>\n WebApplication \u5c06\u6ce8\u518c\u7684\u8def\u7531\u548c\u7ec8\u7aef\u8282\u70b9\u5b58\u50a8\u5728 RoutingMiddleware \u548c EndpointMiddleware \u5171\u4eab\u7684\u5b57\u5178\u4e2d\u3002<\/p>\n TIP<\/b> By default, WebApplication automatically adds the RoutingMiddleware to the start of the middleware and EndpointMiddleware to the end of the middleware pipeline, though you can override the location in the pipeline by calling UseRouting() or UseEndpoints(). See section 4.2.3 for more details about automatically added middleware. At runtime, the RoutingMiddleware compares an incoming request with the routes registered in the dictionary. If the RoutingMiddleware finds a matching endpoint, it makes a note of which endpoint was selected and attaches that to the request\u2019s HttpContext object. Then it calls the next middleware in the pipeline. When the request reaches the EndpointMiddleware, the middleware checks to see which endpoint was selected and executes the endpoint (and any associated endpoint filters), as shown in figure 6.3.<\/p>\n \u5728\u8fd0\u884c\u65f6\uff0cRoutingMiddleware \u5c06\u4f20\u5165\u8bf7\u6c42\u4e0e\u5b57\u5178\u4e2d\u6ce8\u518c\u7684\u8def\u7531\u8fdb\u884c\u6bd4\u8f83\u3002\u5982\u679c RoutingMiddleware \u627e\u5230\u5339\u914d\u7684\u7aef\u70b9\uff0c\u5b83\u4f1a\u8bb0\u4e0b\u9009\u62e9\u4e86\u54ea\u4e2a\u7aef\u70b9\uff0c\u5e76\u5c06\u5176\u9644\u52a0\u5230\u8bf7\u6c42\u7684 HttpContext \u5bf9\u8c61\u3002\u7136\u540e\uff0c\u5b83\u4f1a\u8c03\u7528\u7ba1\u9053\u4e2d\u7684\u4e0b\u4e00\u4e2a\u4e2d\u95f4\u4ef6\u3002\u5f53\u8bf7\u6c42\u5230\u8fbe EndpointMiddleware \u65f6\uff0c\u4e2d\u95f4\u4ef6\u4f1a\u68c0\u67e5\u9009\u62e9\u54ea\u4e2a\u7aef\u70b9\u5e76\u6267\u884c\u8be5\u7aef\u70b9\uff08\u4ee5\u53ca\u4efb\u4f55\u5173\u8054\u7684\u7aef\u70b9\u8fc7\u6ee4\u5668\uff09\uff0c\u5982\u56fe 6.3 \u6240\u793a\u3002<\/p>\n Figure 6.3 Endpoint routing uses a two-step process. The RoutingMiddleware selects which endpoint to execute, and the EndpointMiddleware executes it. If the request URL doesn\u2019t match a route template, the endpoint middleware won\u2019t generate a response. If the request URL doesn\u2019t match a route template, the RoutingMiddleware doesn\u2019t select an endpoint, but the request still continues down the middleware pipeline. As no endpoint is selected, the EndpointMiddleware silently ignores the request and passes it to the next middleware in the pipeline. The EndpointMiddleware is typically the final middleware in the pipeline, so the \u201cnext\u201d middleware is normally the dummy middleware that always returns a 404 Not Found response, as you saw in chapter 4.<\/p>\n \u5982\u679c\u8bf7\u6c42 URL \u4e0e\u8def\u7531\u6a21\u677f\u4e0d\u5339\u914d\uff0c\u5219 RoutingMiddleware \u4e0d\u4f1a\u9009\u62e9\u7ec8\u7aef\u8282\u70b9\uff0c\u4f46\u8bf7\u6c42\u4ecd\u4f1a\u7ee7\u7eed\u6cbf\u4e2d\u95f4\u4ef6\u7ba1\u9053\u5411\u4e0b\u79fb\u52a8\u3002\u7531\u4e8e\u672a\u9009\u62e9\u4efb\u4f55\u7ec8\u7aef\u8282\u70b9\uff0c\u56e0\u6b64 EndpointMiddleware \u4f1a\u9759\u9ed8\u5ffd\u7565\u8be5\u8bf7\u6c42\u5e76\u5c06\u5176\u4f20\u9012\u7ed9\u7ba1\u9053\u4e2d\u7684\u4e0b\u4e00\u4e2a\u4e2d\u95f4\u4ef6\u3002EndpointMiddleware \u901a\u5e38\u662f\u7ba1\u9053\u4e2d\u7684\u6700\u540e\u4e00\u4e2a\u4e2d\u95f4\u4ef6\uff0c\u56e0\u6b64 \u201cnext\u201d \u4e2d\u95f4\u4ef6\u901a\u5e38\u662f\u59cb\u7ec8\u8fd4\u56de 404 Not Found \u54cd\u5e94\u7684\u865a\u62df\u4e2d\u95f4\u4ef6\uff0c\u5982\u7b2c 4 \u7ae0\u6240\u793a\u3002<\/p>\n TIP<\/b> If the request URL doesn\u2019t match a route template, no endpoint is selected or executed. The whole middleware pipeline is still executed, but typically a 404 response is returned when the request reaches the dummy 404 middleware. The advantage of having two separate pieces of middleware to handle this process may not be obvious at first blush. Figure 6.3 hinted at the main benefit: all middleware placed after the RoutingMiddleware can see which endpoint is going to be executed before it is.<\/p>\n \u4f7f\u7528\u4e24\u4e2a\u5355\u72ec\u7684\u4e2d\u95f4\u4ef6\u6765\u5904\u7406\u6b64\u8fc7\u7a0b\u7684\u4f18\u52bf\u4e4d\u4e00\u770b\u53ef\u80fd\u5e76\u4e0d\u660e\u663e\u3002\u56fe 6.3 \u6697\u793a\u4e86\u4e3b\u8981\u7684\u597d\u5904\uff1a\u6240\u6709\u653e\u5728 RoutingMiddleware \u540e\u9762\u7684\u4e2d\u95f4\u4ef6\u90fd\u53ef\u4ee5\u5728\u6267\u884c\u4e4b\u524d\u770b\u5230\u54ea\u4e2a\u7aef\u70b9\u5c06\u88ab\u6267\u884c\u3002<\/p>\n NOTE<\/b> Only middleware placed after the RoutingMiddleware can detect which endpoint is going to be executed. Figure 6.4 shows a more realistic middleware pipeline in which middleware is placed both before the RoutingMiddleware and between the RoutingMiddleware and the EndpointMiddleware.<\/p>\n \u56fe 6.4 \u663e\u793a\u4e86\u4e00\u4e2a\u66f4\u771f\u5b9e\u7684\u4e2d\u95f4\u4ef6\u7ba1\u9053\uff0c\u5176\u4e2d\u4e2d\u95f4\u4ef6\u653e\u7f6e\u5728 RoutingMiddleware \u4e4b\u524d\u4ee5\u53ca RoutingMiddleware \u548c EndpointMiddleware \u4e4b\u95f4\u3002<\/p>\n Figure 6.4 Middleware placed before the routing middleware doesn\u2019t know which endpoint the routing middleware will select. Middleware placed between the routing middleware and the endpoint middleware can see the selected endpoint. The StaticFileMiddleware in figure 6.4 is placed before the RoutingMiddleware, so it executes before an endpoint is selected. Conversely, the AuthorizationMiddleware is placed after the RoutingMiddleware, so it can tell which minimal API endpoint will be executed eventually. In addition, it can access certain metadata about the endpoint, such as its name and the permissions required to access it.<\/p>\n \u56fe 6.4 \u4e2d\u7684 StaticFileMiddleware \u4f4d\u4e8e RoutingMiddleware \u4e4b\u524d\uff0c\u56e0\u6b64\u5b83\u5728\u9009\u62e9\u7aef\u70b9\u4e4b\u524d\u6267\u884c\u3002\u76f8\u53cd\uff0cAuthorizationMiddleware \u4f4d\u4e8e RoutingMiddleware \u4e4b\u540e\uff0c\u56e0\u6b64\u5b83\u53ef\u4ee5\u5224\u65ad\u6700\u7ec8\u5c06\u6267\u884c\u54ea\u4e2a\u6700\u5c0f\u7684 API \u7aef\u70b9\u3002\u6b64\u5916\uff0c\u5b83\u8fd8\u53ef\u4ee5\u8bbf\u95ee\u6709\u5173\u7ec8\u7aef\u8282\u70b9\u7684\u67d0\u4e9b\u5143\u6570\u636e\uff0c\u4f8b\u5982\u5176\u540d\u79f0\u548c\u8bbf\u95ee\u7ec8\u7aef\u8282\u70b9\u6240\u9700\u7684\u6743\u9650\u3002<\/p>\n TIP<\/b> The AuthorizationMiddleware needs to know which endpoint will be executed, so it must be placed after the RoutingMiddleware and before the EndpointMiddleware in your middleware pipeline. I discuss authorization in more detail in chapter 24. It\u2019s important to remember the different roles of the two types of routing middleware when building your application. If you have a piece of middleware that needs to know which endpoint (if any) a given request will execute, you need to make sure to place it after the RoutingMiddleware and before the EndpointMiddleware.<\/p>\n \u5728\u6784\u5efa\u5e94\u7528\u7a0b\u5e8f\u65f6\uff0c\u8bf7\u52a1\u5fc5\u8bb0\u4f4f\u8fd9\u4e24\u79cd\u7c7b\u578b\u7684\u8def\u7531\u4e2d\u95f4\u4ef6\u7684\u4e0d\u540c\u89d2\u8272\u3002\u5982\u679c\u4f60\u6709\u4e00\u4e2a\u4e2d\u95f4\u4ef6\u9700\u8981\u77e5\u9053\u7ed9\u5b9a\u8bf7\u6c42\u5c06\u6267\u884c\u54ea\u4e2a\u7aef\u70b9\uff08\u5982\u679c\u6709\u7684\u8bdd\uff09\uff0c\u4f60\u9700\u8981\u786e\u4fdd\u5c06\u5176\u653e\u5728 RoutingMiddleware \u4e4b\u540e\u548c EndpointMiddleware \u4e4b\u524d\u3002<\/p>\n TIP<\/b> If you want to place middleware before the RoutingMiddleware, such as the StaticFileMiddleware in figure 6.4, you need to override the automatic middleware added by WebApplication by calling UseRouting() at the appropriate point in your middleware pipeline. See listing 4.3 in chapter 4 for an example. I\u2019ve covered how the RoutingMiddleware and EndpointMiddleware interact to provide routing capabilities in ASP.NET Core, but we\u2019ve looked at only simple route templates so far. In the next section we\u2019ll look at some of the many features available with route templates.<\/p>\n \u6211\u5df2\u7ecf\u4ecb\u7ecd\u4e86 RoutingMiddleware \u548c EndpointMiddleware \u5982\u4f55\u4ea4\u4e92\u4ee5\u5728 ASP.NET Core \u4e2d\u63d0\u4f9b\u8def\u7531\u529f\u80fd\uff0c\u4f46\u5230\u76ee\u524d\u4e3a\u6b62\uff0c\u6211\u4eec\u53ea\u4e86\u89e3\u4e86\u7b80\u5355\u7684\u8def\u7531\u6a21\u677f\u3002\u5728\u4e0b\u4e00\u8282\u4e2d\uff0c\u6211\u4eec\u5c06\u4e86\u89e3\u8def\u7531\u6a21\u677f\u63d0\u4f9b\u7684\u4f17\u591a\u529f\u80fd\u4e2d\u7684\u4e00\u4e9b\u3002<\/p>\n So far in this book we\u2019ve looked at simple route templates consisting of fixed values, such as \/person and \/test, as well as using a basic route parameter such as \/fruit\/{id}. In this section we explore the full range of features available in route templates, such as default values, optional segments, and constraints.<\/p>\n \u5230\u76ee\u524d\u4e3a\u6b62\uff0c\u5728\u672c\u4e66\u4e2d\uff0c\u6211\u4eec\u5df2\u7ecf\u4e86\u89e3\u4e86\u7531\u56fa\u5b9a\u503c\u7ec4\u6210\u7684\u7b80\u5355\u8def\u7531\u6a21\u677f\uff0c\u4f8b\u5982 \/person \u548c \/test\uff0c\u4ee5\u53ca\u4f7f\u7528\u57fa\u672c\u8def\u7531\u53c2\u6570\uff0c\u4f8b\u5982\/fruit\/{id} \u4e2d\u3002\u5728\u672c\u8282\u4e2d\uff0c\u6211\u4eec\u5c06\u63a2\u8ba8\u8def\u7531\u6a21\u677f\u4e2d\u63d0\u4f9b\u7684\u5168\u90e8\u529f\u80fd\uff0c\u4f8b\u5982\u9ed8\u8ba4\u503c\u3001\u53ef\u9009\u5206\u6bb5\u548c\u7ea6\u675f\u3002<\/p>\n Route templates have a rich, flexible syntax. Figure 6.5, however, shows a simple example, similar to ones you\u2019ve already seen.<\/p>\n \u8def\u7531\u6a21\u677f\u5177\u6709\u4e30\u5bcc\u3001\u7075\u6d3b\u7684\u8bed\u6cd5\u3002\u7136\u800c\uff0c\u56fe 6.5 \u663e\u793a\u4e86\u4e00\u4e2a\u7b80\u5355\u7684\u4f8b\u5b50\uff0c\u7c7b\u4f3c\u4e8e\u4f60\u5df2\u7ecf\u770b\u5230\u7684\u90a3\u4e9b\u3002<\/p>\n Figure 6.5 A simple route template showing a literal segment and two required route parameters The routing middleware parses a route template by splitting it into segments. A segment is typically separated by the \/ character, but it can be any valid character.<\/p>\n \u8def\u7531\u4e2d\u95f4\u4ef6\u901a\u8fc7\u5c06\u8def\u7531\u6a21\u677f\u62c6\u5206\u4e3a\u6bb5\u6765\u89e3\u6790\u8def\u7531\u6a21\u677f\u3002\u6bb5\u901a\u5e38\u7531\u5b57\u7b26\u5206\u9694\uff0c\u4f46\u5b83\u53ef\u4ee5\u662f\u4efb\u4f55\u6709\u6548\u5b57\u7b26\u3002\/<\/p>\n DEFINITION<\/b> Segments that use a character other than \/ are called complex segments. I generally recommend that you avoid them and stick to using \/ as a separator. Complex segments have some peculiarities that make them hard to use, so be sure to check the documentation at http:\/\/mng.bz\/D4RE<\/a> before you use them. Each segment is either \u2022 A literal value such as product in figure 6.5 \u2022 A route parameter such as {category} and {name} in figure 6.5 The request URL must match literal values exactly (ignoring case). If you need to match a particular URL exactly, you can use a template consisting only of literals.<\/p>\n \u8bf7\u6c42 URL \u5fc5\u987b\u4e0e\u6587\u5b57\u503c\u5b8c\u5168\u5339\u914d\uff08\u5ffd\u7565\u5927\u5c0f\u5199\uff09\u3002\u5982\u679c\u9700\u8981\u7cbe\u786e\u5339\u914d\u7279\u5b9a URL\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ec5\u5305\u542b\u6587\u672c\u7684\u6a21\u677f\u3002<\/p>\n TIP<\/b> Literal segments in ASP.NET Core aren\u2019t case-sensitive. Imagine that you have a minimal API in your application defined using This route template, \u201c\/About\/Contact", consists only of literal values, so it matches only the exact URL (ignoring case). None of the following URLs would match this route template: \u2022 \/about Route parameters are sections of a URL that may vary but are still a match for the template. You define them by giving them a name and placing them in braces, such as {category} or {name}. When used in this way, the parameters are required, so the request URL must have a segment that they correspond to, but the value can vary.<\/p>\n \u8def\u7531\u53c2\u6570\u662f URL \u7684\u90e8\u5206\uff0c\u8fd9\u4e9b\u90e8\u5206\u53ef\u80fd\u4f1a\u6709\u6240\u4e0d\u540c\uff0c\u4f46\u4ecd\u4e0e\u6a21\u677f\u5339\u914d\u3002\u60a8\u53ef\u4ee5\u901a\u8fc7\u4e3a\u5b83\u4eec\u547d\u540d\u5e76\u5c06\u5b83\u4eec\u653e\u5728\u5927\u62ec\u53f7\u4e2d\u6765\u5b9a\u4e49\u5b83\u4eec\uff0c\u4f8b\u5982{\u7c7b\u522b}\u6216 {name} \u7684\u4ee5\u8fd9\u79cd\u65b9\u5f0f\u4f7f\u7528\u65f6\uff0c\u53c2\u6570\u662f\u5fc5\u9700\u7684\uff0c\u56e0\u6b64\u8bf7\u6c42 URL \u5fc5\u987b\u5177\u6709\u5b83\u4eec\u5bf9\u5e94\u7684\u533a\u6bb5\uff0c\u4f46\u8be5\u503c\u53ef\u80fd\u4f1a\u6709\u6240\u4e0d\u540c\u3002<\/p>\n The ability to use route parameters gives you great flexibility. The simple route template "\/{category}\/{name}" could be used to match all the product-page URLs in an e-commerce application: \u2022 \/bags\/rucksack-a\u2014Where category=bags and name=rucksack-a But note that this template would not map the following URLs: \u2022 \/socks\/\u2014No name parameter specified When a route template defines a route parameter and the route matches a URL, the value associated with the parameter is captured and stored in a dictionary of values associated with the request. These route values typically drive other behavior in the endpoint and can be injected into the handlers (as you saw briefly in chapter 5) in a process called model binding.<\/p>\n \u5f53\u8def\u7531\u6a21\u677f\u5b9a\u4e49\u8def\u7531\u53c2\u6570\u5e76\u4e14\u8def\u7531\u4e0e URL \u5339\u914d\u65f6\uff0c\u5c06\u6355\u83b7\u4e0e\u8be5\u53c2\u6570\u5173\u8054\u7684\u503c\u5e76\u5c06\u5176\u5b58\u50a8\u5728\u4e0e\u8bf7\u6c42\u5173\u8054\u7684\u503c\u5b57\u5178\u4e2d\u3002\u8fd9\u4e9b\u8def\u7531\u503c\u901a\u5e38\u9a71\u52a8\u7aef\u70b9\u4e2d\u7684\u5176\u4ed6\u884c\u4e3a\uff0c\u5e76\u4e14\u53ef\u4ee5\u5728\u79f0\u4e3a\u6a21\u578b\u7ed1\u5b9a\u7684\u8fc7\u7a0b\u4e2d\u6ce8\u5165\u5904\u7406\u7a0b\u5e8f\uff08\u5982\u60a8\u5728\u7b2c 5 \u7ae0\u4e2d\u7b80\u8981\u770b\u5230\u7684\u90a3\u6837\uff09\u3002<\/p>\n DEFINITION<\/b> Route values are the values extracted from a URL based on a given route template. Each route parameter in a template has an associated route value, and the values are stored as a string pair in a dictionary. They can be used during model binding, as you\u2019ll see in chapter 7. Literal segments and route parameters are the two cornerstones of ASP.NET Core route templates. With these two concepts, it\u2019s possible to build all manner of URLs for your application. In the remainder of section 6.3 we\u2019ll look at additional features that let you have optional URL segments, provide default values when a segment isn\u2019t specified, and place additional constraints on the values that are valid for a given route parameter.<\/p>\n \u6587\u5b57\u6bb5\u548c\u8def\u7531\u53c2\u6570\u662f ASP.NET Core \u8def\u7531\u6a21\u677f\u7684\u4e24\u4e2a\u57fa\u77f3\u3002\u6709\u4e86\u8fd9\u4e24\u4e2a\u6982\u5ff5\uff0c\u5c31\u53ef\u4ee5\u4e3a\u60a8\u7684\u5e94\u7528\u7a0b\u5e8f\u6784\u5efa\u5404\u79cd URL\u3002\u5728\u7b2c 6.3 \u8282\u7684\u5176\u4f59\u90e8\u5206\u4e2d\uff0c\u6211\u4eec\u5c06\u4ecb\u7ecd\u5176\u4ed6\u529f\u80fd\uff0c\u8fd9\u4e9b\u529f\u80fd\u5141\u8bb8\u60a8\u4f7f\u7528\u53ef\u9009\u7684 URL \u6bb5\uff0c\u5728\u672a\u6307\u5b9a\u6bb5\u65f6\u63d0\u4f9b\u9ed8\u8ba4\u503c\uff0c\u4ee5\u53ca\u5bf9\u7ed9\u5b9a\u8def\u7531\u53c2\u6570\u6709\u6548\u7684\u503c\u8bbe\u7f6e\u5176\u4ed6\u7ea6\u675f\u3002<\/p>\n In section 6.3.1 you saw a simple route template with a literal segment and two required routing parameters. Figure 6.6 shows a more complex route that uses several additional features.<\/p>\n \u5728 6.3.1 \u8282\u4e2d\uff0c\u60a8\u770b\u5230\u4e86\u4e00\u4e2a\u7b80\u5355\u7684\u8def\u7531\u6a21\u677f\uff0c\u5176\u4e2d\u5305\u542b\u4e00\u4e2a\u6587\u5b57\u6bb5\u548c\u4e24\u4e2a\u5fc5\u9700\u7684\u8def\u7531\u53c2\u6570\u3002\u56fe6.6 \u663e\u793a\u4e86\u4e00\u4e2a\u66f4\u590d\u6742\u7684\u8def\u7531\uff0c\u5b83\u4f7f\u7528\u4e86\u51e0\u4e2a\u9644\u52a0\u529f\u80fd\u3002<\/p>\n Figure 6.6 A more complex route template showing literal segments, named route parameters, optional parameters, and default values. The literal product segment and the required {category} parameter are the same as those in in figure 6.6. The {name} parameter looks similar, but it has a default value specified for it by =all. If the URL doesn\u2019t contain a segment corresponding to the {name} parameter, the router will use the all value instead.<\/p>\n \u6587\u672c product segment \u548c\u6240\u9700\u7684 {category}\u53c2\u6570\u4e0e\u56fe 6.6 \u4e2d\u7684\u76f8\u540c\u3002\u8fd9{name} \u53c2\u6570\u770b\u8d77\u6765\u7c7b\u4f3c\uff0c\u4f46\u5b83\u7684\u9ed8\u8ba4\u503c\u7531 =all \u6307\u5b9a\u3002\u5982\u679c URL \u4e0d\u5305\u542b\u4e0e {name} \u53c2\u6570\u5bf9\u5e94\u7684\u6bb5\uff0c\u5219\u8def\u7531\u5668\u5c06\u6539\u7528 all \u503c\u3002<\/p>\n The final segment of figure 6.6, {id?}, defines an optional route parameter called id. This segment of the URL is optional. If this segment is present, the router captures the value for the {id} parameter; if the segment isn\u2019t there, the router doesn\u2019t create a route value for id.<\/p>\n \u56fe 6.6 \u7684\u6700\u540e\u4e00\u6bb5 {id\uff1f} \u5b9a\u4e49\u4e86\u4e00\u4e2a\u540d\u4e3a id \u7684\u53ef\u9009\u8def\u7531\u53c2\u6570\u3002URL \u7684\u6b64\u6bb5\u662f\u53ef\u9009\u7684\u3002\u5982\u679c\u5b58\u5728\u6b64\u6bb5\uff0c\u5219\u8def\u7531\u5668\u5c06\u6355\u83b7 {id} \u53c2\u6570\u7684\u503c;\u5982\u679c segment \u4e0d\u5b58\u5728\uff0c\u5219\u8def\u7531\u5668\u4e0d\u4f1a\u4e3a id \u521b\u5efa route \u503c\u3002<\/p>\n You can specify any number of route parameters in your templates, and these values will be available to you for model binding. The complex route template shown in figure 6.6 allows you to match a greater variety of URLs by making {name} and {id} optional and by providing a default for {name}. Table 6.1 shows some of the URLs that this template would match and the corresponding route values that the router would set.<\/p>\n \u60a8\u53ef\u4ee5\u5728\u6a21\u677f\u4e2d\u6307\u5b9a\u4efb\u610f\u6570\u91cf\u7684\u8def\u7531\u53c2\u6570\uff0c\u8fd9\u4e9b\u503c\u5c06\u53ef\u7528\u4e8e\u6a21\u578b\u7ed1\u5b9a\u3002\u56fe\u4e2d\u6240\u793a\u7684\u590d\u6742\u8def\u7531\u6a21\u677f6.6 \u5141\u8bb8\u60a8\u901a\u8fc7\u4ee5\u4e0b\u65b9\u5f0f\u5339\u914d\u66f4\u591a\u79cd\u7c7b\u7684 URL{\u59d3\u540d}\u548c {id} \u53ef\u9009\uff0c\u5e76\u901a\u8fc7\u4e3a{\u59d3\u540d}\u3002\u8868 6.1 \u663e\u793a\u4e86\u6b64\u6a21\u677f\u5c06\u5339\u914d\u7684\u4e00\u4e9b URL \u4ee5\u53ca\u8def\u7531\u5668\u5c06\u8bbe\u7f6e\u7684\u76f8\u5e94\u8def\u7531\u503c\u3002<\/p>\n Table 6.1 URLs that would match the template of figure 6.7 and their corresponding route values
\n\u5b9a\u4e49<\/strong> ASP.NET Core \u4e2d\u7684\u8def\u7531\u662f\u4e3a\u4f20\u5165\u7684 HTTP \u8bf7\u6c42\u9009\u62e9\u7279\u5b9a\u5904\u7406\u7a0b\u5e8f\u7684\u8fc7\u7a0b\u3002\u5728\u6700\u5c0f API \u4e2d\uff0c\u5904\u7406\u7a0b\u5e8f\u662f\u4e0e\u8def\u7531\u5173\u8054\u7684\u7aef\u70b9\u5904\u7406\u7a0b\u5e8f\u3002\u5728 Razor Pages \u4e2d\uff0c\u5904\u7406\u7a0b\u5e8f\u662f\u5728 Razor Page \u4e2d\u5b9a\u4e49\u7684\u9875\u9762\u5904\u7406\u7a0b\u5e8f\u65b9\u6cd5\u3002\u5728 MVC \u4e2d\uff0c\u5904\u7406\u7a0b\u5e8f\u662f\u63a7\u5236\u5668\u4e2d\u7684\u4f5c\u65b9\u6cd5\u3002<\/p>\n<\/p>\n
\n\u56fe 6.1 \u8def\u7531\u5668\u5c06\u8bf7\u6c42 URL \u4e0e\u5df2\u914d\u7f6e\u7684\u8def\u7531\u6a21\u677f\u5217\u8868\u8fdb\u884c\u6bd4\u8f83\uff0c\u4ee5\u786e\u5b9a\u8981\u6267\u884c\u54ea\u4e2a\u5904\u7406\u7a0b\u5e8f\u3002<\/p>\n\n
\n\u4e3a\u60a8\u7684\u4ea7\u54c1\u7cfb\u5217\u4e2d\u7684\u6bcf\u4e2a\u4ea7\u54c1\u4f7f\u7528\u4e0d\u540c\u7684\u5904\u7406\u7a0b\u5e8f\u3002\u8fd9\u79cd\u65b9\u6cd5\u5bf9\u4e8e\u51e0\u4e4e\u4efb\u4f55\u5b9e\u9645\u89c4\u6a21\u7684\u4ea7\u54c1\u7cfb\u5217\u90fd\u662f\u4e0d\u53ef\u884c\u7684\u3002<\/p>\n<\/li>\n
\n\u4f7f\u7528\u5355\u4e2a\u5904\u7406\u7a0b\u5e8f\uff0c\u5e76\u4f7f\u7528\u67e5\u8be2\u5b57\u7b26\u4e32\u6765\u533a\u5206\u4ea7\u54c1\u3002 \u8fd9\u79cd\u65b9\u6cd5\u8981\u5b9e\u7528\u5f97\u591a\uff0c\u4f46\u60a8\u6700\u7ec8\u4f1a\u5f97\u5230\u4e00\u4e9b\u96be\u770b\u7684 URL\uff0c\u4f8b\u5982\u201c\/product\uff1fname=big-widget\u201c \u6216 \u201d\/product\uff1fid=12\u201c \u7684 API \u7248\u672c\u3002<\/p>\n<\/li>\n<\/ul>\n
\n\u5b9a\u4e49<\/strong> \u67e5\u8be2\u5b57\u7b26\u4e32\u662f URL \u7684\u4e00\u90e8\u5206\uff0c\u5176\u4e2d\u5305\u542b\u4e0d\u9002\u5408\u8def\u5f84\u7684\u5176\u4ed6\u6570\u636e\u3002\u8def\u7531\u57fa\u7840\u8bbe\u65bd\u4e0d\u4f7f\u7528\u5b83\u6765\u6807\u8bc6\u8981\u6267\u884c\u7684\u5904\u7406\u7a0b\u5e8f\uff0c\u4f46 ASP.NET Core \u53ef\u4ee5\u5728\u79f0\u4e3a\u6a21\u578b\u7ed1\u5b9a\u7684\u8fc7\u7a0b\u4e2d\u81ea\u52a8\u4ece\u67e5\u8be2\u5b57\u7b26\u4e32\u4e2d\u63d0\u53d6\u503c\uff0c\u5982\u7b2c 7 \u7ae0\u6240\u793a\u3002\u524d\u9762\u793a\u4f8b\u4e2d\u7684\u67e5\u8be2\u5b57\u7b26\u4e32\u4e3a id=12\u3002<\/p>\n
\n\u6ce8\u610f<\/strong> \u501f\u52a9\u8def\u7531\u7684\u7075\u6d3b\u6027\uff0c\u60a8\u53ef\u4ee5\u5728 URL \u4e2d\u6b63\u786e\u7f16\u7801\u7f51\u7ad9\u7684\u5c42\u6b21\u7ed3\u6784\uff0c\u5982 http:\/\/mng.bz\/EQ2J<\/a> \u7684 Google SEO \u5165\u95e8\u6307\u5357\u4e2d\u6240\u8ff0\u3002<\/p>\n<\/p>\n
\n\u56fe 6.2 \u5982\u679c\u4f7f\u7528\u57fa\u4e8e\u9759\u6001 URL \u7684\u6620\u5c04\uff0c\u5219\u4ea7\u54c1\u8303\u56f4\u4e2d\u7684\u6bcf\u4e2a\u4ea7\u54c1\u90fd\u9700\u8981\u4e0d\u540c\u7684\u5904\u7406\u7a0b\u5e8f\u3002\u4f7f\u7528\u67e5\u8be2\u5b57\u7b26\u4e32\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u5355\u4e2a\u5904\u7406\u7a0b\u5e8f\uff0c\u5e76\u4e14\u67e5\u8be2\u5b57\u7b26\u4e32\u5305\u542b\u6570\u636e\u3002\u4f7f\u7528\u8def\u7531\u65f6\uff0c\u591a\u4e2a URL \u6620\u5c04\u5230\u5355\u4e2a\u5904\u7406\u7a0b\u5e8f\uff0c\u5e76\u4e14\u52a8\u6001\u53c2\u6570\u6355\u83b7 URL \u4e2d\u7684\u5dee\u5f02\u3002<\/p>\n\n
\n\u57fa\u4e8e\u6587\u4ef6\u7cfb\u7edf\u7684\u8def\u7531
\nIn one alternative to routing, the location of a handler on disk dictates the URL you use to invoke it. The downside of this approach is that if you want to change an exposed URL, you also need to change the location of the handler on disk.
\n\u5728\u8def\u7531\u7684\u53e6\u4e00\u79cd\u66ff\u4ee3\u65b9\u6cd5\u4e2d\uff0c\u5904\u7406\u7a0b\u5e8f\u5728\u78c1\u76d8\u4e0a\u7684\u4f4d\u7f6e\u51b3\u5b9a\u4e86\u7528\u4e8e\u8c03\u7528\u5b83\u7684 URL\u3002\u8fd9\u79cd\u65b9\u6cd5\u7684\u7f3a\u70b9\u662f\uff0c\u5982\u679c\u8981\u66f4\u6539\u516c\u5f00\u7684 URL\uff0c\u8fd8\u9700\u8981\u66f4\u6539\u5904\u7406\u7a0b\u5e8f\u5728\u78c1\u76d8\u4e0a\u7684\u4f4d\u7f6e\u3002
\nThis file-based approach may sound like a strange choice, but it has many advantages for some apps, primarily in terms of simplicity. As you\u2019ll see in part 2, Razor Pages is partially file-based but also uses routing to get the best of both worlds!
\n\u8fd9\u79cd\u57fa\u4e8e\u6587\u4ef6\u7684\u65b9\u6cd5\u542c\u8d77\u6765\u53ef\u80fd\u5f88\u5947\u602a\uff0c\u4f46\u5bf9\u4e8e\u67d0\u4e9b\u5e94\u7528\u7a0b\u5e8f\u6765\u8bf4\uff0c\u5b83\u6709\u5f88\u591a\u4f18\u70b9\uff0c\u4e3b\u8981\u662f\u5728\u7b80\u5355\u6027\u65b9\u9762\u3002\u6b63\u5982\u60a8\u5c06\u5728\u7b2c 2 \u90e8\u5206\u4e2d\u770b\u5230\u7684\u90a3\u6837\uff0cRazor Pages \u90e8\u5206\u57fa\u4e8e\u6587\u4ef6\uff0c\u4f46\u4e5f\u4f7f\u7528\u8def\u7531\u6765\u83b7\u5f97\u4e24\u5168\u5176\u7f8e\u7684\u6548\u679c\uff01<\/p>\n<\/blockquote>\n\n
6.2 Endpoint routing in ASP.NET Core<\/h2>\n
6.2 ASP.NET Core \u4e2d\u7684\u7ec8\u7aef\u8282\u70b9\u8def\u7531<\/h2>\n
\n
\nEndpointRoutingMiddleware \u2014 \u6b64\u4e2d\u95f4\u4ef6\u9009\u62e9\u5728\u8fd0\u884c\u65f6\u4e3a\u7ed9\u5b9a\u8bf7\u6c42\u6267\u884c\u54ea\u4e9b\u5df2\u6ce8\u518c\u7684\u7ec8\u7aef\u8282\u70b9\u3002\u4e3a\u4e86\u66f4\u5bb9\u6613\u533a\u5206\u8fd9\u4e24\u79cd\u7c7b\u578b\u7684\u4e2d\u95f4\u4ef6\uff0c\u6211\u5728\u672c\u4e66\u4e2d\u5c06\u6b64\u4e2d\u95f4\u4ef6\u79f0\u4e3a RoutingMiddleware\u3002<\/p>\n<\/li>\n
\nEndpointMiddleware \u2014 \u6b64\u4e2d\u95f4\u4ef6\u901a\u5e38\u4f4d\u4e8e\u4e2d\u95f4\u4ef6\u7ba1\u9053\u7684\u672b\u5c3e\u3002\u4e2d\u95f4\u4ef6\u5728\u8fd0\u884c\u65f6\u6267\u884c RoutingMiddleware \u9009\u62e9\u7684\u7aef\u70b9\u3002<\/p>\n<\/li>\n<\/ul>\n
\n\u5b9a\u4e49<\/em> ASP.NET Core \u4e2d\u7684\u7ec8\u7aef\u8282\u70b9\u662f\u8fd4\u56de\u54cd\u5e94\u7684\u5904\u7406\u7a0b\u5e8f\u3002\u6bcf\u4e2a\u7aef\u70b9\u90fd\u4e0e\u4e00\u4e2a URL \u6a21\u5f0f\u76f8\u5173\u8054\u3002\u6839\u636e\u8981\u751f\u6210\u7684\u5e94\u7528\u7a0b\u5e8f\u7c7b\u578b\uff0c\u6700\u5c11\u7684 API \u5904\u7406\u7a0b\u5e8f\u3001Razor Page \u5904\u7406\u7a0b\u5e8f\u6216 MVC \u63a7\u5236\u5668\u4f5c\u65b9\u6cd5\u901a\u5e38\u6784\u6210\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684\u5927\u90e8\u5206\u7ec8\u7ed3\u70b9\u3002\u4f8b\u5982\uff0c\u60a8\u8fd8\u53ef\u4ee5\u4f7f\u7528\u7b80\u5355\u7684\u4e2d\u95f4\u4ef6\u4f5c\u4e3a\u7ec8\u7aef\u8282\u70b9\uff0c\u6216\u8005\u60a8\u53ef\u4ee5\u4f7f\u7528\u8fd0\u884c\u72b6\u51b5\u68c0\u67e5\u7ec8\u7aef\u8282\u70b9\u3002<\/p>\n\n
\n\u4f7f\u7528 MapGet\uff08\uff09 \u7684\u6700\u5c0f API \u5904\u7406\u7a0b\u5e8f\uff0c\u5982\u524d\u51e0\u7ae0\u6240\u793a\u3002<\/p>\n<\/li>\n
\n\u4f7f\u7528 MapHealthChecks\uff08\uff09 \u7684\u8fd0\u884c\u72b6\u51b5\u68c0\u67e5\u7ec8\u7aef\u8282\u70b9\u3002\u60a8\u53ef\u4ee5\u5728 http:\/\/mng.bz\/N2YD<\/a> \u4e0a\u9605\u8bfb\u6709\u5173\u8fd0\u884c\u72b6\u51b5\u68c0\u67e5\u7684\u66f4\u591a\u4fe1\u606f\u3002<\/p>\n<\/li>\n
\n\u4f7f\u7528 MapRazorPages\uff08\uff09 \u7684\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684\u6240\u6709 Razor Pages \u7ec8\u7ed3\u70b9\u3002\u60a8\u5c06\u5728\u7b2c 14 \u7ae0\u4e2d\u4e86\u89e3\u6709\u5173\u4f7f\u7528 Razor Pages \u8fdb\u884c\u8def\u7531\u7684\u66f4\u591a\u4fe1\u606f\u3002<\/p>\n<\/li>\n<\/ul>\n
\n\u6e05\u5355 6.1 \u4f7f\u7528 \u6ce8\u518c\u591a\u4e2a\u7aef\u70b9Web\u5e94\u7528\u7a0b\u5e8f<\/p>\n\nWebApplicationBuilder builder = WebApplication.CreateBuilder(args);\nbuilder.Services.AddHealthChecks(); \/\/ \u2776\nbuilder.Services.AddRazorPages(); \/\/ \u2776\n\nWebApplication app = builder.Build();\n\napp.MapGet("\/test", () => "Hello world!"); \/\/ \u2777\napp.MapHealthChecks("\/healthz"); \/\/ \u2778\napp.MapRazorPages(); \/\/ \u2779\n\napp.Run();\n<\/pre>\n
\n\u6dfb\u52a0\u8fd0\u884c\u72b6\u51b5\u68c0\u67e5\u4e2d\u95f4\u4ef6\u548c Razor Pages \u6240\u9700\u7684\u670d\u52a1<\/p>\n
\n\u6ce8\u518c\u4e00\u4e2a\u6700\u5c0f\u7684 API \u7aef\u70b9\uff0c\u8be5\u7aef\u70b9\u5728\u8def\u7531 \/test \u4e2d\u8fd4\u56de \u201cHello World\uff01\u201d<\/p>\n
\n\u5728\u8def\u7531 \/healthz \u4e2d\u6ce8\u518c\u4e00\u4e2a\u5065\u5eb7\u68c0\u67e5\u7aef\u70b9<\/p>\n
\n\u5c06\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684\u6240\u6709 Razor Pages \u6ce8\u518c\u4e3a\u7aef\u70b9<\/p>\n
\n\u5b9a\u4e49\uff1a \u8def\u7531\u6a21\u677f\u662f\u4e00\u79cd URL \u6a21\u5f0f\uff0c\u7528\u4e8e\u5339\u914d\u8bf7\u6c42 URL\uff0c\u8bf7\u6c42 URL \u662f\u56fa\u5b9a\u503c\u7684\u5b57\u7b26\u4e32\uff0c\u5982\u4e0a\u4e00\u4e2a\u5217\u8868\u4e2d\u7684 \u201c\/test\u201d\u3002 \u5b83\u4eec\u8fd8\u53ef\u4ee5\u5305\u542b\u53d8\u91cf\u7684\u5360\u4f4d\u7b26\uff0c\u5982 6.3 \u8282\u6240\u793a\u3002<\/p>\n
\n\u63d0\u793a\uff1a \u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0cWebApplication \u4f1a\u81ea\u52a8\u5c06 RoutingMiddleware \u6dfb\u52a0\u5230\u4e2d\u95f4\u4ef6\u7684\u5f00\u5934\uff0c\u5c06 EndpointMiddleware \u6dfb\u52a0\u5230\u4e2d\u95f4\u4ef6\u7ba1\u9053\u7684\u672b\u5c3e\uff0c\u4f46\u60a8\u53ef\u4ee5\u901a\u8fc7\u8c03\u7528 UseRouting\uff08\uff09 \u6216 UseEndpoints\uff08\uff09 \u6765\u8986\u76d6\u7ba1\u9053\u4e2d\u7684\u4f4d\u7f6e\u3002\u6709\u5173\u81ea\u52a8\u6dfb\u52a0\u7684\u4e2d\u95f4\u4ef6\u7684\u66f4\u591a\u8be6\u7ec6\u4fe1\u606f\uff0c\u8bf7\u53c2\u89c1 Section 4.2.3\u3002<\/p>\n<\/p>\n
\n\u56fe 6.3 \u7ec8\u7aef\u8282\u70b9\u8def\u7531\u4f7f\u7528\u4e24\u6b65\u8fc7\u7a0b\u3002RoutingMiddleware \u9009\u62e9\u8981\u6267\u884c\u7684\u7aef\u70b9\uff0cEndpointMiddleware \u6267\u884c\u5b83\u3002\u5982\u679c\u8bf7\u6c42 URL \u4e0e\u8def\u7531\u6a21\u677f\u4e0d\u5339\u914d\uff0c\u5219\u7ec8\u7aef\u8282\u70b9\u4e2d\u95f4\u4ef6\u4e0d\u4f1a\u751f\u6210\u54cd\u5e94\u3002<\/p>\n
\n\u63d0\u793a\uff1a \u5982\u679c\u8bf7\u6c42 URL \u4e0e\u8def\u7531\u6a21\u677f\u4e0d\u5339\u914d\uff0c\u5219\u4e0d\u4f1a\u9009\u62e9\u6216\u6267\u884c\u4efb\u4f55\u7ec8\u7aef\u8282\u70b9\u3002\u6574\u4e2a\u4e2d\u95f4\u4ef6\u7ba1\u9053\u4ecd\u7136\u4f1a\u6267\u884c\uff0c\u4f46\u5f53\u8bf7\u6c42\u5230\u8fbe\u865a\u62df 404 \u4e2d\u95f4\u4ef6\u65f6\uff0c\u901a\u5e38\u4f1a\u8fd4\u56de 404 \u54cd\u5e94\u3002<\/p>\n
\n\u6ce8\u610f\uff1a \u53ea\u6709\u653e\u5728 RoutingMiddleware \u4e4b\u540e\u7684 middleware \u624d\u80fd\u68c0\u6d4b\u5230\u5c06\u8981\u6267\u884c\u7684\u7aef\u70b9\u3002<\/p>\n<\/p>\n
\n\u56fe 6.4 \u653e\u7f6e\u5728\u8def\u7531\u4e2d\u95f4\u4ef6\u524d\u9762\u7684\u4e2d\u95f4\u4ef6\u4e0d\u77e5\u9053\u8def\u7531\u4e2d\u95f4\u4ef6\u5c06\u9009\u62e9\u54ea\u4e2a\u7aef\u70b9\u3002\u653e\u7f6e\u5728\u8def\u7531\u4e2d\u95f4\u4ef6\u548c\u7ec8\u7aef\u8282\u70b9\u4e2d\u95f4\u4ef6\u4e4b\u95f4\u7684\u4e2d\u95f4\u4ef6\u53ef\u4ee5\u770b\u5230\u6240\u9009\u7ec8\u7aef\u8282\u70b9\u3002<\/p>\n
\n\u63d0\u793a\uff1a AuthorizationMiddleware \u9700\u8981\u77e5\u9053\u5c06\u6267\u884c\u54ea\u4e2a\u7aef\u70b9\uff0c\u56e0\u6b64\u5b83\u5fc5\u987b\u653e\u5728\u4e2d\u95f4\u4ef6\u7ba1\u9053\u4e2d\u7684 RoutingMiddleware \u4e4b\u540e\u548c EndpointMiddleware \u4e4b\u524d\u3002\u6211\u5728\u7b2c 24 \u7ae0\u4e2d\u66f4\u8be6\u7ec6\u5730\u8ba8\u8bba\u4e86\u6388\u6743\u3002<\/p>\n
\n\u63d0\u793a\uff1a \u5982\u679c\u4f60\u60f3\u628a\u4e2d\u95f4\u4ef6\u653e\u5728 RoutingMiddleware \u4e4b\u524d\uff0c\u6bd4\u5982\u56fe 6.4 \u4e2d\u7684 StaticFileMiddleware\uff0c\u4f60\u9700\u8981\u5728\u4e2d\u95f4\u4ef6\u7ba1\u9053\u4e2d\u7684\u9002\u5f53\u4f4d\u7f6e\u8c03\u7528 UseRouting\uff08\uff09 \u6765\u8986\u76d6 WebApplication \u6dfb\u52a0\u7684\u81ea\u52a8\u4e2d\u95f4\u4ef6\u3002\u6709\u5173\u793a\u4f8b\uff0c\u8bf7\u53c2\u89c1\u7b2c 4 \u7ae0\u4e2d\u7684\u6e05\u5355 4.3\u3002<\/p>\n6.3 Exploring the route template syntax<\/h2>\n
6.3 \u63a2\u7d22\u8def\u7531\u6a21\u677f\u8bed\u6cd5<\/h2>\n
6.3.1 Working with parameters and literal segments<\/h3>\n
6.3.1 \u4f7f\u7528\u53c2\u6570\u548c\u6587\u672c\u6bb5<\/h3>\n
<\/p>\n
\n\u56fe 6.5 \u4e00\u4e2a\u7b80\u5355\u7684\u8def\u7531\u6a21\u677f\uff0c\u5176\u4e2d\u663e\u793a\u4e86\u4e00\u4e2a\u6587\u672c\u6bb5\u548c\u4e24\u4e2a\u5fc5\u9700\u7684\u8def\u7531\u53c2\u6570<\/p>\n
\n\u5b9a\u4e49\uff1a \u4f7f\u7528\u5176\u4ed6\u5b57\u7b26\u7684\u7ebf\u6bb5\u79f0\u4e3a\u590d\u6742\u7ebf\u6bb5\u3002\u6211\u901a\u5e38\u5efa\u8bae\u60a8\u907f\u514d\u4f7f\u7528\u5b83\u4eec\u5e76\u575a\u6301\u7528\u4f5c\u5206\u9694\u7b26\u3002\u590d\u6742\u533a\u6bb5\u5177\u6709\u4e00\u4e9b\u7279\u6027\uff0c\u4f7f\u5176\u96be\u4ee5\u4f7f\u7528\uff0c\u56e0\u6b64\u8bf7\u52a1\u5fc5\u5728\u4f7f\u7528 http:\/\/mng.bz\/D4RE<\/a> \u4e4b\u524d\u67e5\u770b\u6587\u6863\u3002<\/p>\n
\n\u6bcf\u4e2a\u6bb5\u662f<\/p>\n
\n\u5982\u56fe 6.5 \u6240\u793a\u7684 Literal \u503cproduct<\/p>\n
\n\u8def\u7531\u53c2\u6570\uff0c\u5982\u56fe 6.5 \u4e2d\u7684 \u548c{category}{name}<\/p>\n
\n\u63d0\u793a\uff1a ASP.NET Core \u4e2d\u7684\u6587\u672c\u6bb5\u4e0d\u533a\u5206\u5927\u5c0f\u5199\u3002<\/p>\n
\n\u5047\u8bbe\u60a8\u5728\u5e94\u7528\u7a0b\u5e8f\u4e2d\u6709\u4e00\u4e2a\u4f7f\u7528<\/p>\n\napp.MapGet("\/About\/Contact", () => {\/* *\/})\n<\/pre>\n
\n\u6b64\u8def\u7531\u6a21\u677f \u201c\/About\/Contact\u201d \u4ec5\u5305\u542b\u6587\u672c\u503c\uff0c\u56e0\u6b64\u5b83\u4ec5\u5339\u914d\u786e\u5207\u7684 URL\uff08\u5ffd\u7565\u5927\u5c0f\u5199\uff09\u3002\u4ee5\u4e0b URL \u90fd\u4e0d\u5339\u914d\u6b64\u8def\u7531\u6a21\u677f\uff1a<\/p>\n
\n\u2022 \/about-us\/contact
\n\u2022 \/about\/contact\/email
\n\u2022 \/about\/contact-us<\/p>\n
\n\u4f7f\u7528\u8def\u7531\u53c2\u6570\u7684\u80fd\u529b\u4e3a\u60a8\u63d0\u4f9b\u4e86\u6781\u5927\u7684\u7075\u6d3b\u6027\u3002\u7b80\u5355\u7684\u8def\u7531\u6a21\u677f \u201c\/{category}\/{name}\u201d \u53ef\u7528\u4e8e\u5339\u914d\u7535\u5b50\u5546\u52a1\u5e94\u7528\u7a0b\u5e8f\u4e2d\u7684\u6240\u6709\u4ea7\u54c1\u9875\u9762 URL\uff1a<\/p>\n
\n\u2022 \/shoes\/black-size9\u2014Where category=shoes and name=black-size9<\/p>\n
\n\u4f46\u8bf7\u6ce8\u610f\uff0c\u6b64\u6a21\u677f\u4e0d\u4f1a\u6620\u5c04\u4ee5\u4e0b URL\uff1a<\/p>\n
\n\u2022 \/trousers\/mens\/formal\u2014Extra URL segment, formal, not found in route template<\/p>\n
\n\u5b9a\u4e49\uff1a \u8def\u7531\u503c \u662f\u6839\u636e\u7ed9\u5b9a\u8def\u7531\u6a21\u677f\u4ece URL \u4e2d\u63d0\u53d6\u7684\u503c\u3002\u6a21\u677f\u4e2d\u7684\u6bcf\u4e2a\u8def\u7531\u53c2\u6570\u90fd\u6709\u4e00\u4e2a\u5173\u8054\u7684\u8def\u7531\u503c\uff0c\u8fd9\u4e9b\u503c\u4f5c\u4e3a\u5b57\u7b26\u4e32\u5bf9\u5b58\u50a8\u5728\u5b57\u5178\u4e2d\u3002\u5b83\u4eec\u53ef\u4ee5\u5728\u6a21\u578b\u7ed1\u5b9a\u671f\u95f4\u4f7f\u7528\uff0c\u5982\u7b2c 7 \u7ae0\u6240\u793a\u3002<\/p>\n6.3.2 Using optional and default values<\/h3>\n
6.3.2 \u4f7f\u7528\u53ef\u9009\u503c\u548c\u9ed8\u8ba4\u503c<\/h3>\n
<\/p>\n
\n\u56fe 6.6 \u4e00\u4e2a\u66f4\u590d\u6742\u7684\u8def\u7531\u6a21\u677f\uff0c\u663e\u793a\u6587\u672c\u6bb5\u3001\u547d\u540d\u8def\u7531\u53c2\u6570\u3001\u53ef\u9009\u53c2\u6570\u548c\u9ed8\u8ba4\u503c\u3002<\/p>\n
\n\u8868 6.1 \u4e0e\u56fe 6.7 \u4e2d\u7684\u6a21\u677f\u5339\u914d\u7684 URL \u53ca\u5176\u76f8\u5e94\u7684\u8def\u7531\u503c<\/p>\n
![\"\"](\"\/images\/aspnetcoreinaction\/0607.png\")
<\/p>\n![\"\"](\"\/images\/aspnetcoreinaction\/0608.png\")
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