vb.net不等到所有任務完成

所以我正在處理記錄。我正在使用任務來處理每條記錄。我的問題是我的程序在所有任務完成之前完成。任何任何想法，我在做什麼錯在這裏？vb.net不等到所有任務完成

 Dim task As Task 

     Try 
      'Keep looping until no more requests to run have been made    
      Do 
       Dim controller As New Controller() 
       Dim record As Record = controller.GetNextRecord() 

       If record IsNot Nothing Then 

        'Use Task! 
        task = Task.Factory.StartNew(Sub() controller.ProcessRecord(record), TaskCreationOptions.LongRunning) 
        CalledWhenBusy = True 
       End If 
     TryAgain: 
      Loop Until ProcessAgain() = False 


     Catch ex As System.Net.WebException 
      logger.ErrorException("unable to connect to remoting server", ex) 

     Finally 
      logger.Info("Processed all records.. now about to wait for all tasks to complete") 
      'Wait till all tasks have stopped running 
      Task.WaitAll(task) 

      logger.Info("Processed all records.. All tasks have completed") 
      'The dispatcher has finished for now so clean up 
      Me.StopUsing() 
     End Try 




Private Function ProcessAgain() As Boolean 

    If CalledWhenBusy Then 
     'Reset the flag and exit with true 
     CalledWhenBusy = False 
     Return True 
    End If 

    Return False 

End Function

UPDATE

通過@HansPassant的建議和@usr

之所以不使用的foreach我已經通過任務列表解決了我的問題，是更多的紀錄可以在處理時添加..因此，儘管while循環...

謝謝你的幫助。

  Dim taskList = New List(Of Task)() 

     Try 
      'Keep looping until no more requests to run have been made    
      Do 
       Dim controller As New Controller() 
       Dim record As Record = controller.GetNextRecord() 

       If record IsNot Nothing Then 

        'Use Task! 
        taskList.Add(Task.Factory.StartNew(Sub() controller.ProcessRecord(record))) 
        CalledWhenBusy = True 
       End If 
TryAgain: 
      Loop Until ProcessAgain() = False 


     Catch ex As System.Net.WebException 
      logger.ErrorException("unable to connect to remoting server", ex) 

     Finally 
      logger.Info("Processed all records.. now about to wait for all tasks to complete") 
      'Wait till all tasks have stopped running 
      Task.WaitAll(taskList.ToArray()) 

      logger.Info("Processed all records.. All tasks have completed") 
      'The dispatcher has finished for now so clean up 
      Me.StopUsing() 
     End Try

來源

2016-03-10 Fiona

foreach比做更好的解決方案。我猜測它沒有捕捉任何東西。再次過程如何？ – Claudius

我同意重新捕捉，（現有的代碼 - 我第一次看它），我會更新它。 – Fiona

很不清楚你如何編譯。您應該將任務的*數組*傳遞給WaitAll（）。通過創建一個List（Of Task）開始解決這個問題。並且要注意LongRunning，如果你有超過幾十條記錄，那麼這臺機器會非常困難。 –

Task.WaitAll(task)正在等待一個任務。其他人在哪裏？你甚至存儲過它們嗎？從這段代碼中看不出來。

理想情況下，您可以轉換此代碼，以便它可以使用Parallel.ForEach。您需要將工作項目轉換爲IEnumerable格式才能正常工作。例如，將它們添加到List並將列表提供給Parallel.ForEach。

來源

2016-03-10 13:28:36 usr

vb.net不等到所有任務完成

回答

相關問題