private void button_Click(object sender, RoutedEventArgs e) { try { bl.AddOrderedDish(d); MessageBox.Show("ordered dish " + d.orderNumber + " dish number: " + d.amountOfDish + " amount: " + d.amountOfDish + " was added"); //MessageBox.Show("הוספה בהצלחה" + d.orderNumber + " מנה מוזמנת "); if (bl.freedesert(d.orderNumber)) { MessageBox.Show("A free deset was added to your order"); } d = new BE.Ordered_Dish(); this.DataContext = d; orderNumberComboBox.SelectedValue = d.orderNumber; dishNumberComboBox.SelectedValue = d.dishNumber; } catch (Exception ex) { MessageBox.Show(ex.Message); } }