private void btLO_Click(object sender, RoutedEventArgs e)
        {
            LesOnderwerpCMS lo = new LesOnderwerpCMS(user);

            lo.Show();
            this.Close();
        }
        private void btOpslaan_Click(object sender, RoutedEventArgs e)
        {
            string sVakNaam = "";

            switch (VakID)
            {
            case "1":
                sVakNaam = "Geschiedenis";
                break;

            case "2":
                sVakNaam = "Rekenen";
                break;

            case "3":
                sVakNaam = "Biologie";
                break;

            case "4":
                sVakNaam = "Nederlands";
                break;

            case "5":
                sVakNaam = "Engels";
                break;
            }

            Class.VoegLesOnderwerpToe(VakID, tbNaam.Text);
            MessageBox.Show("Het les onderwerp is toegevoegd aan " + sVakNaam + ".", "Succes!");

            LesOnderwerpCMS form = new LesOnderwerpCMS();

            form.Show();
            this.Close();
        }
        private void btTerug_Click(object sender, RoutedEventArgs e)
        {
            LesOnderwerpCMS terug = new LesOnderwerpCMS(user);

            terug.Show();
            this.Close();
        }
        private void btOpslaan_Click(object sender, RoutedEventArgs e)
        {
            Class.VoegLesOnderwerpToe(VakID, tbNaam.Text);

            LesOnderwerpCMS form = new LesOnderwerpCMS(user);

            form.Show();
            this.Close();
        }
 public LesonderwerpToevoegen(LesOnderwerpCMS form, string SelectedVakID)
 {
     InitializeComponent();
     lastform = form;
     VakID    = SelectedVakID;
 }