public decimal Total() { if (Basket != null && !Basket.Any()) { throw new NullReferenceException(); } CalculateTotal(); return(Basket.Sum(p => p.Price)); }
private void AddToBasket(object sender, RoutedEventArgs e) { string s = (sender as Button).Content.ToString(); Product product = Products.First((Product p) => p.ProductName.Equals(s)); if (!Basket.Any(b => b.Product.ID == product.ID)) { Basket.Add(new ReceiptLine { Amount = 1, Product = product, TotalPrice = product.UnitPrice }); } else { ReceiptLine receiptLine = Basket.First(p => p.Product.ID == product.ID); receiptLine.Amount++; receiptLine.TotalPrice += product.UnitPrice; } TotalSum = Basket.Sum(p => p.TotalPrice); }