ASP.NET购物车实现分析

如何在购物车中存储数据？

cart=new datatable();

    /// <summary>
    /// 新建购物车
    /// </summary>
    public void BuildCart(Product product) {
        DataTable cart = new DataTable();
        DataColumn[] dc = new DataColumn[] { 
            new DataColumn("Id"),
            new DataColumn("Name"),
            new DataColumn("buyCount"),
            new DataColumn("Price"),
            new DataColumn("Picture"),
            new DataColumn("Number"),
            new DataColumn("SellNumber")
        };
        cart.Columns.AddRange(dc);
        BuildSession(cart, product);
    }

    /// <summary>
    /// 添加新商品
    /// </summary>
    /// <param name="cart"></param>
    public void BuildSession(DataTable cart, Product product) {
        DataRow dr = cart.NewRow();
        dr[0] = product.Id;
        dr[1] = product.Name;
        dr[2] = "1";
        dr[3] = product.Price;
        dr[4] = product.Picture;
        dr[5] = product.Number;
        dr[6] = product.SellNumber;
        cart.Rows.Add(dr);
        HttpContext.Current.Session[SESSION_CAR] = cart;
    }

public DataTable GetCar() {
        if (HttpContext.Current.Session[SESSION_CAR] != null) {
            DataTable car = HttpContext.Current.Session[SESSION_CAR] as DataTable;
            return car;
        }
        else {
            return null;
        }
    }

    /// <summary>
    /// 计算总价
    /// </summary>
    /// <param name="cart"></param>
    public double TotalPrice(DataTable cart) {
        double total = 0;
        foreach (DataRow dr in cart.Rows) {
            total += Convert.ToDouble(dr["Price"]) * (Convert.ToInt32(dr[2].ToString()));
        }
        return total;
    }