某些服务无法使用Blazor Server构建

Question

我有 class CustomersService：icustomersService

带有contractor：

public CustomersService(HttpClient http)
{
   this._http = http;
}

in program.cs file ：

builder.Services.AddScoped<ICustomersService, CustomersService>();

我应该如何重新启动/重置构造函数？

Builder.Services.AddScoped＆lt; icustomersService，customersService＆gt;（）; 错误是：

invalidoperationException：无法解析type'system.net.http.httpclient'

Answer 1

我猜想您在Blazor Server中，因为httpclient在Web Assembly中默认注册。

这是我在服务器中进行操作的方式：

// Server Side Blazor doesn't register HttpClient by default
// Thanks to Robin Sue - Suchiman https://github.com/Suchiman/BlazorDualMode
if (!services.Any(x => x.ServiceType == typeof(HttpClient))
{
     // Setup HttpClient for server side in a client side compatible fashion
     services.AddScoped<HttpClient>(s =>
    {
       // Creating the URI helper needs to wait until the JS Runtime is initialized, so defer it.
       var uriHelper = s.GetRequiredService<NavigationManager>();
       return new HttpClient
       {
          BaseAddress = new Uri(uriHelper.BaseUri)
       };
   });
}