public FrmVerificationTransfertClient() { InitializeComponent(); ChargerListDesSite(); List <string> ListOperation = new List <string>(); ListOperation = SessionObject.TypeOperationClasseur().ToList(); tab4_cbo_Operation.ItemsSource = null; tab4_cbo_Operation.ItemsSource = ListOperation; if (ListOperation != null && ListOperation.Count != 0) { tab4_cbo_Operation.SelectedItem = ListOperation[0]; } prgBar.Visibility = System.Windows.Visibility.Collapsed; RemplirCodeRegroupement(); }