Question

我有一个产生多个线程的线程。如何确定所有线程是否完成？所有线程完成后我必须调用一个方法。这不是重复的喜欢

dim thread1.start()
dim thread2.start()
if (all threads are finished)
muFunc()
end if

您可以在下方看到示例代码段。 see the code here

这就是我被困的地方。我该怎么办？提前谢谢。

Answer 1

从任何地方调用此方法（Form.Load，Button.Click ...）
调用者事件处理程序/方法不需要是异步调用者

ThreadPoolManager()

定义包含线程池的List(Of Thread)的范围

Dim ThreadPool As List(Of Thread)

ThreadPoolManager()（a）等待StartThreads()，它启动ThreadPool列表中的所有线程。 Async方法返回时，然后调用MyFunctionWhenAllThreadsAreFinished()

  Private Async Sub ThreadPoolManager()

     If Await StartThreads() = True Then
        MsgBox("All Finished!", MsgBoxStyle.OkOnly, "Finally!")
        Call MyFunctionWhenAllThreadsAreFunished()
     Else
        MsgBox("Something went wrong!", MsgBoxStyle.OkOnly, "Damn it!")
     End If
  End Sub

StartThreads()方法初始化ThreadPool中的所有线程，并使用委托工作方法在线程启动时调用

  Protected Async Function StartThreads() As Task(Of Boolean)
     ThreadPool = New List(Of Thread)
     Dim MyThread1 As Thread = New Thread(AddressOf Me.MyThread1Work)
     Dim MyThread2 As Thread = New Thread(AddressOf Me.MyThread2Work)

     ThreadPool.AddRange({MyThread1, MyThread2})

     For Each _PT As Thread In ThreadPool : _PT.Start() : Next

     Return Await Task.Run(Function()
                             Dim AllFinished As Integer
                             While AllFinished < ThreadPool.Count
                                AllFinished = 0
                                For Each _T As Thread In ThreadPool
                                   If _T.IsAlive = False Then AllFinished += 1
                                Next
                             End While
                             Console.WriteLine("All Thread Finished")
                          Return True
                       End Function)
  End Function


  Private Sub MyThread1Work(_Obj As Object)
     Thread.Sleep(5000)
     Console.WriteLine("Thread 1 Finished")
  End Sub

  Private Sub MyThread2Work(_Obj As Object)
     Thread.Sleep(7000)
     Console.WriteLine("Thread 2 Finished")
  End Sub

如何在vb.net中使用多线程来识别线程是在运行还是已完成

1 个答案: