错误详情:已取消该操作。--------- 在 System.Threading.CancellationToken.ThrowOperationCanceledException()

错误详情:已取消该操作。--------- 在 System.Threading.CancellationToken.ThrowOperationCanceledException()
在 System.Net.Http.HttpContentExtensions.<ReadAsAsyncCore>d__0`1.MoveNext()
--- 引发异常的上一位置中堆栈跟踪的末尾 ---
在 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
在 System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
在 System.Web.Http.ModelBinding.FormatterParameterBinding.<ExecuteBindingAsyncCore>d__0.MoveNext()
--- 引发异常的上一位置中堆栈跟踪的末尾 ---
在 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
在 System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
在 System.Web.Http.Controllers.HttpActionBinding.<ExecuteBindingAsyncCore>d__0.MoveNext()
--- 引发异常的上一位置中堆栈跟踪的末尾 ---
在 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
在 System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
在 System.Web.Http.Controllers.ActionFilterResult.<ExecuteAsync>d__2.MoveNext()
--- 引发异常的上一位置中堆栈跟踪的末尾 ---
在 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
在 System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
在 System.Web.Http.Controllers.ExceptionFilterResult.<ExecuteAsync>d__0.MoveNext()

　　

尝试如下操作：
config.MessageHandlers.Add(new CancelledTaskBugWorkaroundMessageHandler());

class CancelledTaskBugWorkaroundMessageHandler : DelegatingHandler
{
protected override async Task SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
HttpResponseMessage response = await base.SendAsync(request, cancellationToken);

    // Try to suppress response content when the cancellation token has fired; ASP.NET will log to the Application event log if there's content in this case.
    if (cancellationToken.IsCancellationRequested)
    {
        return new HttpResponseMessage(HttpStatusCode.InternalServerError);
    }

    return response;
}

}