我使用 WebClient 从我的 MVC5 项目的外部网站获取数据:
using (var client = new WebClient())
{
var result = client.DownloadString(url);
return this.Content(result);
}
然而,请求的URL使用TLS,但我们处于开发阶段,所以他们使用他们自己的证书,这显然是不合法的。因此,我收到此异常:
[IOException: Authentication failed because the remote party has closed the transport stream.]
System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest) +6587998
System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest) +132
System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest) +59
System.Net.Security.SslState.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest) +247
System.Net.Security.SslState.ForceAuthentication(Boolean receiveFirst, Byte[] buffer, AsyncProtocolRequest asyncRequest) +137
System.Net.Security.SslState.ProcessAuthentication(LazyAsyncResult lazyResult) +119
System.Net.TlsStream.CallProcessAuthentication(Object state) +38
System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx) +166
System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx) +21
System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state) +64
System.Net.TlsStream.ProcessAuthentication(LazyAsyncResult result) +797
System.Net.TlsStream.Write(Byte[] buffer, Int32 offset, Int32 size) +52
System.Net.PooledStream.Write(Byte[] buffer, Int32 offset, Int32 size) +19
System.Net.ConnectStream.WriteHeaders(Boolean async) +142
我已经阅读了许多其他文章,所以我将这些代码添加到我的 Global.asax
Application_Start
方法中:
System.Net.ServicePointManager.ServerCertificateValidationCallback =
(s, cert, chain, sslPolicyErrors) =>
{
return true;
};
然而,结果保持不变。我什至尝试将断点放在 Callback set 行,并将 1 放在 return true
行。开始时,断点按预期命中。但是,当 WebClient 调用时,永远不会命中 return true
行的断点。
WebClient
是否使用了另一种 CallBack 方法?我该如何解决这个问题?
最佳答案
问题是你必须添加这样的东西
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls11
| SecurityProtocolType.Tls12;
但这取决于它支持的协议(protocol)。你可以在这里查看 https://www.ssllabs.com
这个结果是我从这个网站上得到的 协议(protocol)
TLS 1.2 Yes TLS 1.1 Yes TLS 1.0 No SSL 3 No SSL 2 No
关于c# - WebClient 忽略 ServicePointManager.ServerCertificateValidationCallback?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27225263/