public ActionResult AddItems(long storeId, long[] selectedIds) { var store = _storeRepository.GetById(storeId); foreach (var id in selectedIds) { var existed = store.StoreItems.Any(s => s.ItemId == id); if (!existed) { var storeItem = _storeService.AddStoreItem(storeId, id); store.StoreItems.Add(storeItem); } } this._dbContext.SaveChanges(); return(new NullJsonResult()); }