Protected Sub Frame1_OnClosing(ByVal sender As Object, ByVal e As _
      System.ComponentModel.CancelEventArgs) Handles MyBase.Closing
      If me.DialogResult = DialogResult.OK Then
        If MeineBedingung = False Then
          MessageBox.Show(me, "Fehler" );
          e.Cancel = True;
        End If
      End If
    End Sub