Xamarin异步Http客户端

Question

我的Xamarin项目遇到了问题：当我尝试从网页上获取JsonString时，通过HttpClient.GetStringAsncy我的应用程序崩溃了。这是错误的StackTrace：

  at System.Net.Http.HttpClientHandler+d__63.MoveNext () [0x00479] in :0 
--- End of stack trace from previous location where exception was thrown ---
  at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0003e] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x00028] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x00008] in :0 
  at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in :0 
  at System.Net.Http.HttpClient+d__49.MoveNext () [0x000ca] in :0 
--- End of stack trace from previous location where exception was thrown ---
  at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0003e] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x00028] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x00008] in :0 
  at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in :0 
  at System.Net.Http.HttpClient+d__54.MoveNext () [0x0007d] in :0 
--- End of stack trace from previous location where exception was thrown ---
  at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0003e] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x00028] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x00008] in :0 
  at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in :0 
  at MRKrauchthal.Pages.GameDetailPage+d__13.MoveNext () [0x00057] in E:\Visual Studio Projects\MRKrauchthal\MRKrauchthal\MRKrauchthal\Pages\GameDetailPage.xaml.cs:99 

e.InnerException

{System.Net.WebException: Error: SecureChannelFailure (The authentication or decryption has failed.) ---> System.IO.IOException: The authentication or decryption has failed. ---> System.IO.IOException: The authentication or decryption has failed. ---> Mono.Security.Protocol.Tls.TlsException: The authentication or decryption has failed.
  at Mono.Security.Protocol.Tls.RecordProtocol.EndReceiveRecord (System.IAsyncResult asyncResult) [0x00037] in :0 
  at Mono.Security.Protocol.Tls.SslClientStream.SafeEndReceiveRecord (System.IAsyncResult ar, System.Boolean ignoreEmpty) [0x00000] in :0 
  at Mono.Security.Protocol.Tls.SslClientStream.NegotiateAsyncWorker (System.IAsyncResult result) [0x00071] in :0 
   --- End of inner exception stack trace ---
  at Mono.Security.Protocol.Tls.SslClientStream.EndNegotiateHandshake (System.IAsyncResult result) [0x00032] in :0 
  at Mono.Security.Protocol.Tls.SslStreamBase.AsyncHandshakeCallback (System.IAsyncResult asyncResult) [0x0000c] in :0 
   --- End of inner exception stack trace ---
  at Mono.Security.Protocol.Tls.SslStreamBase.EndRead (System.IAsyncResult asyncResult) [0x0004b] in :0 
  at Mono.Net.Security.Private.LegacySslStream.EndAuthenticateAsClient (System.IAsyncResult asyncResult) [0x0000e] in :0 
  at Mono.Net.Security.Private.LegacySslStream.AuthenticateAsClient (System.String targetHost, System.Security.Cryptography.X509Certificates.X509CertificateCollection clientCertificates, System.Security.Authentication.SslProtocols enabledSslProtocols, System.Boolean checkCertificateRevocation) [0x0000e] in :0 
  at Mono.Net.Security.MonoTlsStream.CreateStream (System.Byte[] buffer) [0x0007b] in :0 
  at System.Net.WebConnection.CreateStream (System.Net.HttpWebRequest request) [0x00073] in :0 
   --- End of inner exception stack trace ---
  at System.Net.HttpWebRequest.EndGetResponse (System.IAsyncResult asyncResult) [0x00058] in :0 
  at System.Threading.Tasks.TaskFactory`1[TResult].FromAsyncCoreLogic (System.IAsyncResult iar, System.Func`2[T,TResult] endFunction, System.Action`1[T] endAction, System.Threading.Tasks.Task`1[TResult] promise, System.Boolean requiresSynchronization) [0x0000f] in :0 
--- End of stack trace from previous location where exception was thrown ---
  at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0003e] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x00028] in :0 
  at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x00008] in :0 
  at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in :0 
  at System.Net.Http.HttpClientHandler+d__63.MoveNext () [0x0041e] in :0 }

代码如下：

private async Task SetImage(int id, string teamName, Xamarin.Forms.Image image)
    {
        try
        {
            HttpClient httpClient = new HttpClient();
            obj = JsonConvert.DeserializeObject<JsonImage>(await httpClient.GetStringAsync("www.linkToImage.com").ConfigureAwait(false));
        }
        catch (Exception e) {
            test.Text = e.StackTrace;
        }

    }

我希望有人可以帮助我：D

最好的问候

Answer 1

Xamarin.Android中的默认SSL / TLS实现存在一些问题。您可以转到Android 项目设置 - ＆gt; Android选项 - ＆gt;高级 - ＆gt; SSL / TLS实施，然后更改为 Native TLS 1.2 +