private void buttonAjouter_Click(object sender, EventArgs e)
 {
     if (textBoxPrenom.Text != "")
     {
         var selectedEntree  = (CarteMenuModel)comboBoxEntree.SelectedItem;
         var selectedPlat    = (CarteMenuModel)comboBoxPlat.SelectedItem;
         var selectedDessert = (CarteMenuModel)comboBoxDessert.SelectedItem;
         var selectedMenu    = (MenuModel)comboBoxMenu.SelectedItem;
         helper.idEntree         = selectedEntree.idCarteRestaurant;
         helper.idPlat           = selectedPlat.idCarteRestaurant;
         helper.idDessert        = selectedDessert.idCarteRestaurant;
         helper.prixParPersonnes = Convert.ToInt32((Manage.GetPrixGroupe(selectedEntree.idCarteRestaurant) + Manage.GetPrixGroupe(selectedPlat.idCarteRestaurant) + Manage.GetPrixGroupe(selectedDessert.idCarteRestaurant)) * 0.9);
         if (Manage.GetDetailReservation().Exists(x => x.idDetailReservation == helper.idDetail))
         {
             Manage.ModifierDetailReservationMenu(helper.idDetail, textBoxPrenom.Text, helper.idEntree, helper.idPlat, helper.idDessert, helper.prixParPersonnes, selectedMenu.idMenu);
         }
         else
         {
             Manage.AjouteDetailReservationMenu(GetIdReservation(), textBoxPrenom.Text, helper.idEntree, helper.idPlat, helper.idDessert, helper.prixParPersonnes, selectedMenu.idMenu);
         }
         this.Hide();
         NouvelleReservationCommande oNouvelleReservationCommande = new NouvelleReservationCommande();
         oNouvelleReservationCommande.Closed   += (s, args) => this.Close();
         oNouvelleReservationCommande.MdiParent = this.MdiParent;
         oNouvelleReservationCommande.Show();
     }
     else
     {
         MessageBox.Show("Veuillez introduire un prénom !");
     }
 }