WebException: 基础连接已经关闭: 连接被意外关闭。
--Status: ConnectionClosed
StackTrace:
   在 System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
   在 DynamicClass.WebDAVClient.FinishList(IAsyncResult result)
   在 System.Net.LazyAsyncResult.Complete(IntPtr userToken)
   在 System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   在 System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   在 System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   在 System.Net.ContextAwareResult.Complete(IntPtr userToken)
   在 System.Net.LazyAsyncResult.ProtectedInvokeCallback(Object result, IntPtr userToken)
   在 System.Net.HttpWebRequest.SetResponse(Exception E)
   在 System.Net.ConnectionReturnResult.SetResponses(ConnectionReturnResult returnResult)
   在 System.Net.Connection.ReadComplete(Int32 bytesRead, WebExceptionStatus errorStatus)
   在 System.Net.LazyAsyncResult.Complete(IntPtr userToken)
   在 System.Net.ContextAwareResult.Complete(IntPtr userToken)
   在 System.Net.LazyAsyncResult.ProtectedInvokeCallback(Object result, IntPtr userToken)
   在 System.Net.Sockets.BaseOverlappedAsyncResult.CompletionPortCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* nativeOverlapped)
   在 System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* pOVERLAP)