public void StartAsync(object userState) { Reset(userState); this.IsBusy = true; AsynchronousOperationHandler handler = new AsynchronousOperationHandler(this.AsynchronousOperation); handler.BeginInvoke(null, null, userState); AsyncOperation operation = (AsyncOperation)userStates[userState]; operation.Post(new SendOrPostCallback(PostStarted), new AsynchronousActionsEventArgs()); }