HttpClient.GetStringAsync(url) 抛出 "The underlying connection was closed: An unexpected error occurred on a send." Windows 8.1 C#

Question

我正在创建一个新的 Windows 8.1 应用程序，只是为了测试我遇到的这个错误。 该应用程序只有一个功能：

private async void TestMethod()
        {
            try
            {                       
                HttpClient httpClient = new HttpClient();
                HttpResponseMessage response = await httpClient.GetAsync("https:// url ");                    
            }
            catch (HttpRequestException e)
            {
                string s = e.InnerException.Message;
            }
        }

它总是进入捕获并抛出 "The underlying connection was closed: An unexpected error occurred on a send." 我发现很多问题都提到了这一点，但没有解决方案对我有用，因为这是一个 Windows 8.1 商店应用程序而不是 ASP.NET 应用程序。

我正在使用的 Uri 在浏览器中打开并且运行良好。

我什至看到了这篇文章：https://support.microsoft.com/en-us/kb/915599 但没有解决方案。有人遇到过这个问题吗？

编辑：

我把方法改成了async Task

System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a send. ---> System.IO.IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. ---> System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host
  at System.Net.Sockets.Socket.EndReceive(IAsyncResult asyncResult)
  at System.Net.Sockets.NetworkStream.EndRead(IAsyncResult asyncResult)
  --- End of inner exception stack trace ---
  at System.Net.TlsStream.EndWrite(IAsyncResult asyncResult)
  at System.Net.PooledStream.EndWrite(IAsyncResult asyncResult)
  at System.Net.ConnectStream.WriteHeadersCallback(IAsyncResult ar)
  --- End of inner exception stack trace ---
  at System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
  at System.Net.Http.HttpClientHandler.GetResponseCallback(IAsyncResult ar)
  --- End of inner exception stack trace ---
  at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
  at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
  at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
  at HttpRequestTestApp.MainPage.d__0.MoveNext()

Answer 1

原来我使用的 Windows.Net.Http 不支持 TLS1.2。 Windows.Web.Http 确实如此。