public bool Save() { try { int pizzaMaxId = Pizzas.Max(u => u.Id); int toppingMaxId = Toppings.Max(u => u.Id); int idIncrementer = 1; foreach (var np in Pizzas.Where(u => u.Id == 0)) { np.Id = pizzaMaxId + idIncrementer; idIncrementer++; } idIncrementer = 0; foreach (var nt in Toppings.Where(u => u.Id == 0)) { nt.Id = toppingMaxId + idIncrementer; idIncrementer++; } Helper.Serialize(Constants.DB_PIZZA_PATH, new DbPizza() { Pizzas = Pizzas }); Helper.Serialize(Constants.DB_TOPPING_PATH, new DbTopping() { Toppings = Toppings }); return(true); } catch (Exception ex) { return(false); } }