o_19mgorv9t13a3ko71fev19l81mqa.pdf

Continue Shopping button to return to the product catalog, or click the Checkout Now button to complete the
order and finish the shopping session.
Defining the Cart Entity
A shopping cart is part of the business domain, so it makes sense to represent a cart by creating an entity in the domain model.
Add a class file called Cart.cs to the Entities folder in the SportsStore.Domain project and use it to define
the classes shown in Listing 8-12.
Listing 8-12. The Cart and CartLine Classes in the Cart.cs File
using System.Collections.Generic;
using System.Linq;
namespace SportsStore.Domain.Entities {
public class Cart {
private List lineCollection = new List();
public void AddItem(Product product, int quantity) {
CartLine line = lineCollection
.Where(p => p.Product.ProductID == product.ProductID)
.FirstOrDefault();
}
if (line == null) {
lineCollection.Add(new CartLine { Product = product,
Quantity = quantity });
} else {
line.Quantity += quantity;
}
public void RemoveLine(Product product) {
lineCollection.RemoveAll(l => l.Product.ProductID ==
product.ProductID);
}
public decimal ComputeTotalValue() {
return lineCollection.Sum(e => e.Product.Price * e.Quantity);
}
public void Clear() {
lineCollection.Clear();
}
}
public IEnumerable Lines {
get { return lineCollection; }
}
}
public class CartLine {
public Product Product { get; set; }
public int Quantity { get; set; }
}
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