Question

我在SignalR Server的事件查看器上发现了以下错误，我无法理解可能导致这种情况的原因。有提示吗？

An unhandled exception occurred and the process was terminated.

Exception: System.NullReferenceException

Message: Object reference not set to an instance of an object.

StackTrace:    at Microsoft.AspNet.SignalR.Client.Transports.ServerSentEventsTransport.OnStartFailed()
   at System.Action.Invoke()
   at Microsoft.AspNet.SignalR.Client.Infrastructure.TransportInitializationHandler.<>c__DisplayClasse.<CompleteFail>b__d()
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()
   at System.Threading.ThreadPoolWorkQueue.Dispatch()

Answer 1

这是一个错误。更多细节here。目前已分配在2.2.1中修复。

Answer 2

根据堆栈跟踪和OnStartFailed()方法中的the code来判断我猜测它在SignalR内部存在一些线程问题\竞争条件。你能做的最好的就是在SignalR Github上报告......

SignalR Hub：未处理的异常

2 个答案: