请教各位怎实现:点击按键启动新线程,再点击一下则关闭上一线程(即使任务还未完成),紧接着又一启动新线程

请问各位怎实现:点击按键启动新线程,再点击一下则关闭上一线程(即使任务还未完成),紧接着又一启动新线程
如题所示.谢谢!(环境vb.net)

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这样做不是很好。最好考虑在线程里用线程同步方式，实现功能切换，一定要这么做，就把线程对象保存起来，判断
IsActive，就Kill掉。不论如何都重新启动。
如果不知道如何做。再回复，我再贴给你代码。
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Private thList As New List(Of Thread)

Private Sub button3_Click(ByVal sender As Object, ByVal e As EventArgs)
Dim th As New Thread(New ParameterizedThreadStart(AddressOf Me.ThreadProc))
Me.thList.Add(th)
th.Start(Me.thList.Count)
End Sub

Private Sub button4_Click(ByVal sender As Object, ByVal e As EventArgs)
Do While (Me.thList.Count > 0)
If Me.thList.Item(0).IsAlive Then
Me.thList.Item(0).Abort
Me.thList.RemoveAt(0)
End If
Loop
End Sub

Private Sub ThreadProc(ByVal obj As Object)
Dim i As Integer = CInt(obj)
Do While True
MyBase.Invoke(New MyDeleage(AddressOf Me.AddThreadID), New Object() { i })
Thread.Sleep(50)
Loop
End Sub

Private Sub AddThreadID(ByVal i As Integer)
Me.textBox1.Text = (Me.textBox1.Text & i.ToString)
End Sub
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楼上说的对!!!