using System.Collections.Generic; using System.Linq; namespace Microsoft.eShopWeb.ApplicationCore.Entities { public class Basket : BaseEntity { public string BuyerId { get; set; } private readonly List _items = new List(); public IEnumerable Items => _items.ToList(); public void AddItem(int catalogItemId, decimal unitPrice, int quantity = 1) { if (!Items.Any(i => i.CatalogItemId == catalogItemId)) { _items.Add(new BasketItem() { CatalogItemId = catalogItemId, Quantity = quantity, UnitPrice = unitPrice }); return; } var existingItem = Items.FirstOrDefault(i => i.CatalogItemId == catalogItemId); existingItem.Quantity += quantity; } } }