Private t As Thread
    Private f2 As New Form2
    Private run As Boolean
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        f2 = New Form2
        run = True
        t = New Thread(AddressOf DoWork)
        t.Start()
    End Sub
 
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button2.Click
        run = False
        While t.IsAlive
            Application.DoEvents()
        End While
    End Sub
 
    Private Sub ShowF2()
        f2.Show()
    End Sub
 
    Private Sub CloseF2()
        f2.Close()
        f2 = Nothing
    End Sub
 
    Private Delegate Sub UpdateListBoxHandler(ByVal item As String)
 
    Private Sub UpdateListBox(ByVal item As String)
        f2.ListBox1.Items.Add(item)
    End Sub
 
    Private Sub DoWork()
        Dim i As Integer
        Me.Invoke(New MethodInvoker(AddressOf Me.ShowF2))
 
        While run
            i += 1
            Thread.Sleep(1000)
            Me.Invoke(New UpdateListBoxHandler(AddressOf UpdateListBox), New _
              Object() {"Item" & i.ToString()})
        End While
 
        Me.Invoke(New MethodInvoker(AddressOf Me.CloseF2))
    End Sub

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