private void ui_submit_Click(object sender, RoutedEventArgs e) { int season; try { season = Int32.Parse(ui_seasons.Text); } catch { MessageBox.Show("Seasons must be a positive number"); return; } if (season <= 0) { MessageBox.Show("Seasons must be a positive number"); return; } if (ui_cardnumber.Text.Length != 16) { MessageBox.Show("Credit card number must be 16 digits."); return; } estate.AddAdvertisement(new Advertisement(estate, DateTime.Now.Year + season)); MainWindow.Instance.ChangeView("views/owner/AdvertiseEstateList.xaml"); }