问题可能是出现在此处，因为Blazor WebAssembly不能访问本地网络资源。需要确保在Program.cs中注册了Http客户端，并允许非安全请求。

例如：

builder.Services.AddScoped(sp => new HttpClient { 
    BaseAddress = new Uri(builder.HostEnvironment.BaseAddress) })
    .AddHttpMessageHandler();

// For server-side Blazor, authentication is configured in Startup.cs.
builder.Services.AddOidcAuthentication(options =>
{
    // Configure your authentication provider options here.
    // For more information, see https://aka.ms/blazor-standalone-auth
    builder.Configuration.Bind("Local", options.ProviderOptions);
});

基于需要，您还可以添加其他配置选项。这是保证 HttpClient能够在 Blazor WebAssembly中执行调用所必需的步骤。

参考：https://docs.microsoft.com/en-us/aspnet/core/blazor/security/webassembly/standalone-with-authentication-library?view=aspnetcore-5.0&tabs=visual-studio