没有找到HttpClient BaseAddressAuthorizationMessageHandler

Question

我正在尝试使用本文向我的。net 5 Blazor WASM应用程序添加身份验证，但是我得到了一个错误

Unhandled exception rendering component: No service for type 'Microsoft.AspNetCore.Components.WebAssembly.Authentication.BaseAddressAuthorizationMessageHandler' has been registered.

我从git这里下载了样本，运行它，一切都工作了，然后我注意到样本是在。net 3中完成的，当我更新它运行在。net 5时，同样的错误正在悄然上升。在我的Program.cs中，我像这样注册了HttpClient和BaseAddressAuthorizationMessageHandler

  public static async Task Main(string[] args)
  {
     var builder = WebAssemblyHostBuilder.CreateDefault(args);
     builder.RootComponents.Add<App>("app");
     builder.Services.AddHttpClient("ServerAPI",
        client => client.BaseAddress = new Uri(builder.HostEnvironment.BaseAddress))
     .AddHttpMessageHandler<BaseAddressAuthorizationMessageHandler>();
     builder.Services.AddScoped(sp => sp.GetRequiredService<IHttpClientFactory>()
         .CreateClient("ServerAPI"));
     builder.Services.AddBlazoredLocalStorage();
     builder.Services.AddAuthorizationCore();
     builder.Services.AddScoped<AuthenticationStateProvider, ApiAuthenticationStateProvider>();
     builder.Services.AddScoped<IAuthService, AuthService>();
     await builder.Build().RunAsync();
  }

我认为这是一个错误，你可以看到我添加BaseAddressAuthorizationMessageHandler到客户端，就像它显示在这里，有什么我错过了?是否有需要导入的名称空间，或者是否缺少配置的另一部分?断点似乎在客户端的Program.cs中不起作用，我没有看到任何其他错误可以解释这一点。

Answer 1

一旦我弄清楚发生了什么，这是一个相当容易的修复，当授权设置像这样显然你不需要添加BaseAddressAuthorizationMessageHandler到客户端，因为这个例子是手动设置HTTP请求头通过AuthService

  public static async Task Main(string[] args)
  {
     var builder = WebAssemblyHostBuilder.CreateDefault(args);
     builder.RootComponents.Add<App>("app");
     builder.Services.AddHttpClient("ServerAPI",
        client => client.BaseAddress = new Uri(builder.HostEnvironment.BaseAddress));
     builder.Services.AddScoped(sp => sp.GetRequiredService<IHttpClientFactory>()
         .CreateClient("ServerAPI"));
     builder.Services.AddBlazoredLocalStorage();
     builder.Services.AddAuthorizationCore();
     builder.Services.AddScoped<AuthenticationStateProvider, ApiAuthenticationStateProvider>();
     builder.Services.AddScoped<IAuthService, AuthService>();
     await builder.Build().RunAsync();
  }