通过调用'iservicecollection.addhealthchecks'添加所有必需的服务

我正在使用ASP.NET Core 3,.NET Core 3.0.100,Visual Studio 2019社区。我遵循这个指南 https://docs.microsoft.com/en-us/aspnet/core/release-notes/aspnetcore-3.0?view=aspnetcore-3.0#health-checks

在 Startup.cs ,我补充说 endpoints.MapHealthChecks("/health");

        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {         

            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
                app.UseDatabaseErrorPage();
            }
            else
            {
                app.UseExceptionHandler("/Error");
                // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
                app.UseHsts();
            }
            app.UseHttpsRedirection();
            app.UseStaticFiles();
            app.UseRouting();
            app.UseAuthentication();
            app.UseAuthorization();
            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
                endpoints.MapRazorPages();
                endpoints.MapBlazorHub();
                endpoints.MapFallbackToPage("/_Host");
                endpoints.MapHealthChecks("/health");
            });
        }
    }
}

错误

System.InvalidOperationException
  HResult=0x80131509
  Message=Unable to find the required services. Please add all the required services by calling 'IServiceCollection.AddHealthChecks' inside the call to 'ConfigureServices(...)' in the application startup code.
  Source=Microsoft.AspNetCore.Diagnostics.HealthChecks
  StackTrace:
   at Microsoft.AspNetCore.Builder.HealthCheckEndpointRouteBuilderExtensions.MapHealthChecksCore(IEndpointRouteBuilder endpoints, String pattern, HealthCheckOptions options)
   at Microsoft.AspNetCore.Builder.HealthCheckEndpointRouteBuilderExtensions.MapHealthChecks(IEndpointRouteBuilder endpoints, String pattern)
   at acc133blazor.Startup.<>c.<Configure>b__5_0(IEndpointRouteBuilder endpoints) in C:\Users\donhuvy\Desktop\acc133b3\acc133blazor\Startup.cs:line 104
   at Microsoft.AspNetCore.Builder.EndpointRoutingApplicationBuilderExtensions.UseEndpoints(IApplicationBuilder builder, Action`1 configure)
   at acc133blazor.Startup.Configure(IApplicationBuilder app, IWebHostEnvironment env) in C:\Users\donhuvy\Desktop\acc133b3\acc133blazor\Startup.cs:line 98
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor, Boolean wrapExceptions)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at Microsoft.AspNetCore.Hosting.ConfigureBuilder.Invoke(Object instance, IApplicationBuilder builder)
   at Microsoft.AspNetCore.Hosting.ConfigureBuilder.<>c__DisplayClass4_0.<Build>b__0(IApplicationBuilder builder)
   at Microsoft.AspNetCore.Hosting.GenericWebHostBuilder.<>c__DisplayClass13_0.<UseStartup>b__2(IApplicationBuilder app)
   at Microsoft.AspNetCore.Mvc.Filters.MiddlewareFilterBuilderStartupFilter.<>c__DisplayClass0_0.<Configure>g__MiddlewareFilterBuilder|0(IApplicationBuilder builder)
   at Microsoft.AspNetCore.Server.IIS.Core.IISServerSetupFilter.<>c__DisplayClass2_0.<Configure>b__0(IApplicationBuilder app)
   at Microsoft.AspNetCore.HostFilteringStartupFilter.<>c__DisplayClass0_0.<Configure>b__0(IApplicationBuilder app)
   at Microsoft.AspNetCore.Hosting.GenericWebHostService.<StartAsync>d__31.MoveNext()

怎么解决?