Private Sub TextBox_Enter(ByVal sender As Object, ByVal e As _
      System.EventArgs) Handles TextBox1.Enter, TextBox2.Enter, TextBox3.Enter, _
      TextBox4.Enter, TextBox5.Enter
        Dim tb As TextBox = CType(sender, TextBox)
        tb.HideSelection = False
        tb.SelectAll()
        tb.HideSelection = True
    End Sub