第一个匹配路由必须同时指定控制器和动作？

Question

下面是我的代码：

//inside UseMvc method:
routes.MapRoute(
   name: "NewRoute",
   template: "/",
   defaults: new { controller = "Home"});

routes.MapRoute(
   name: "default",
    template: "{controller=Home}/{action=Index}/{id?}");

我们知道路由系统只会找到第一个匹配的路由，所以第一个'NewRoute'应该在应用程序启动时匹配路由，因为它没有action方法，所以我应该得到一个404错误页面，但是当我运行应用程序时，使用了 "default" 路由，显示正常页面。那么为什么 "NewRoute" 没有首先被路由系统选中？

Answer 1

事实是先检查NewRoute，但是路由找不到匹配的action.Then它将匹配下一个路由规则。

如果在 appSettings.Development.json

中将日志记录级别设为 Debug

{
"Logging": {
  "LogLevel": {
    "Default": "Debug",
    "System": "Information",
    "Microsoft": "Debug"
  }
}
}

并将启动的CompatibilityVersion改为2.1（asp.net core 2.2有另一种EndPoint机制）

services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);

当你运行应用程序时，你可以在日志中看到整个过程：

dbug: Microsoft.AspNetCore.Routing.RouteBase[1]
      Request successfully matched the route with name 'NewRoute' and template '/'
dbug: Microsoft.AspNetCore.Mvc.Internal.ActionSelector[3]
      No actions matched the current request. Route values: controller=Home
dbug: Microsoft.AspNetCore.Mvc.Internal.MvcRouteHandler[3]
      No actions matched the current request. Route values: controller=Home
dbug: Microsoft.AspNetCore.Routing.RouteBase[1]
      Request successfully matched the route with name 'default' and template '{controller=Home}/{action=Index}/{id?}'
info: Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker[3]
      Route matched with {action = "Index", controller = "Home"}. Executing controller action with signature Microsoft.AspNetCore.Mvc.IActionResult Index() on controller Core22MVC.Controllers.HomeController (Core22MVC).

它匹配两次 select default 路由。

第一个匹配路由必须同时指定控制器和动作？

first match routes must specify both controller and action?

c#

asp.net-mvc-routing

asp.net-core