private void UpdateDish(GetReservedDish_Result oldDish, Dish newDish) {
   using(ProjetSGBDEntities context = new ProjetSGBDEntities()) {
     if(oldDish != null) {
       if((newDish != null) && (oldDish.DishId != newDish.DishId)) {
         context.DeleteReservedDish(oldDish.ClientId, oldDish.DishId, CurrentReception.ReceptionId, oldDish.ModifiedAt);
         context.NewReservedDish(CurrentClient.Id, newDish.DishId, CurrentReception.ReceptionId, CurrentClient.Acronym);
       }
     } else {
       if(newDish != null) {
         context.NewReservedDish(CurrentClient.Id, newDish.DishId, CurrentReception.ReceptionId, CurrentClient.Acronym);
       }
     }
   }
 }