private void btnKlant_Click(object sender, RoutedEventArgs e)
        {
            ucKlant go = new ucKlant();

            gInhoud.Children.Clear();
            gInhoud.Children.Add(go);
        }
        private void btnMbestelling_Click(object sender, RoutedEventArgs e)
        {
            ucKlant go = new ucKlant();

            mGrid.Children.Clear();
            mGrid.Children.Add(go);
        }