docs(Upload): Improve Upload controller documentation

components/upload/events.md

@@ -783,6 +783,8 @@ var builder = WebApplication.CreateBuilder(args);
 
 // ...
 
+builder.Services.AddControllers();
+
 var app = builder.Build();
 
 // ...

components/upload/overview.md

@@ -69,14 +69,17 @@ Steps 4 and 5 are optional, but strongly recommended.
     * The correct binding source attribute for the file name argument is `[FromForm]`. Set it explicitly if you are using an [`[ApiController]` attribute](https://learn.microsoft.com/en-gb/aspnet/core/web-api/).
     * Use the Upload [`OnRemove` event](slug:upload-events#onremove) to [send additional custom data with the file](slug:upload-events#send-custom-data-with-the-file) as an argument to the `Remove` controller method.
 
-Both action methods must accept `POST` requests. Correct request routing depends on the application.
+Both action methods must accept `POST` requests.
 
-The `UploadController` class below assumes that the project name and namespace is `TelerikBlazorUpload`.
+Request routing depends on the application and it outside the Upload component's scope. Normally, the following two statements in the server project's `Program.cs` are enough:
 
-Make sure to enable controller routing in the app startup file (`Program.cs`). In this case, `app.MapDefaultControllerRoute();` is all that's needed.
+* `builder.Services.AddControllers();`
+* `app.MapDefaultControllerRoute();`.
 
 Also check the [Upload Troubleshooting](slug:upload-troubleshooting) page.
 
+The `UploadController` class below assumes that the project name and namespace is `TelerikBlazorUpload`.
+
 >caption Sample Upload Controller
 
 <div class="skip-repl"></div>

components/upload/troubleshooting.md

@@ -26,7 +26,7 @@ The action method is hit, but the method argument is `null`
 
 ## HTTP 400 Bad request
 
-The action method is not hit and the server returns HTTP 400 Bad request.
+The action method is not hit and the server returns `HTTP 400 Bad request`.
 
 * Make sure that [controller routing is enabled and configured correctly](https://docs.microsoft.com/en-us/aspnet/core/mvc/controllers/routing). For example, the controller samples in this documentation use `[Route("api/[controller]/[action]")]`. It is enough to add `app.MapDefaultControllerRoute();` to `Program.cs` in the default Blazor project template. [Web API controllers require explicit `[Route]` configuration](https://learn.microsoft.com/en-gb/aspnet/core/web-api/?view=aspnetcore-8.0#attribute-routing-requirement).
 * Make sure that the `[Route]` attribute in the upload controller (if set) is compatible with `SaveUrl` and `RemoveUrl`.
@@ -41,6 +41,16 @@ The Remove action may return `HTTP 415 Unsupported Media Type`.
 This means that the Remove action method expects `IEnumerable<string>` and .NET does not infer the correct binding source. Set a `[FromForm]` [binding source attribute](https://learn.microsoft.com/en-gb/aspnet/core/web-api/?view=aspnetcore-8.0#binding-source-parameter-inference) to the file name argument.
 
 
+## HTTP 405 Method Not Allowed
+
+The action method is not hit and the server returns `HTTP 405 Method not allowed`.
+
+Make sure that [controller routing is enabled](https://learn.microsoft.com/en-us/aspnet/core/tutorials/first-web-api) in the server-side project's startup file (`Program.cs`). Normally, the following two statements are required:
+
+* `builder.Services.AddControllers();`
+* `app.MapDefaultControllerRoute();`.
+
+
 ## Connection Error and No Response
 
 The server does not return any response. The browser console shows connection errors like: