public Result AddToFavorites(string userId, string productId) { var cart = _confirmUserCartExistedDomainService.GetUserCart(userId); if (cart.IsEmpty()) { return(Result.Fail("当前购物车中并没有商品")); } var cartItem = cart.GetCartItem(productId); if (cartItem == null) { return(Result.Fail("该购物项已不存在")); } var favorites = DomainRegistry.FavoritesRepository().GetByUserId(userId) ?? new Favorites(userId, null); favorites.AddFavoritesItem(cartItem); DomainRegistry.FavoritesRepository().Save(favorites); return(Result.Success()); }