private void BTN_modifierLoco_Click(object sender, RoutedEventArgs e)
        {
            if (DG_listeLoco.SelectedItem == null)
            {
                return;
            }

            CLoco objLoco = (CLoco)DG_listeLoco.SelectedItem;
            fenetreLoco fenetreLoco = new fenetreLoco(gestionTrain, objLoco);
        }
 // boutons loco
 private void BTN_ajoutLoco_Click(object sender, RoutedEventArgs e)
 {
     fenetreLoco fenetreLoco = new fenetreLoco(gestionTrain);
 }