Private Sub MyButton_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        Debug.WriteLine("Click aus einem MDI Fenster")
    End Sub
    Private Sub btnOpenMDIChild_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles btnOpenMDIChild.Click
        Dim f As New frmMdiChild
        AddHandler f.Button1.Click, New EventHandler(AddressOf _
          Me.MyButton_Click)
        f.MdiParent = Me
        f.Show()
    End Sub