Dim _guid As Guid = System.Guid.NewGuid()

  Private TaskThreads As New Hashtable()

Public Sub startMyWorker(ByVal host As String)
            Dim gd As New GetData(host)
            AddHandler gd.GetDataCompleted, AddressOf myWorkCompleted
 
            Dim myWorkerThread As New Thread(AddressOf gd.doWork)
            myWorkerThread.Start()
 
            TaskThreads.Add(gd.Guid.ToString(), myWorkerThread)
End sub

        Dim TaskThread As Thread
        Dim item As DictionaryEntry
 
        For Each item In TaskThreads
            TaskThread = CType(item.Value, Thread)
            If (TaskThread.ThreadState And ThreadState.Running) = _
              ThreadState.Running Then
                TaskThread.Abort()
            End If
        Next