public bool AddToCart(int userId, int productId, int featureValueId, int num) { if (userId <= 0 || productId <= 0 || featureValueId <= 0) { return(false); } using (var cxt = DbContext(DbOperation.Write)) { cxt.BeginTransaction(); var repo = new ShoppingCartRepo(cxt); var flag = repo.AddToCart(userId, productId, featureValueId, num); if (flag) { cxt.Commit(); } else { cxt.Rollback(); } return(flag); } }