购物车代码

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Collections;
public partial class AddCar : System.Web.UI.Page
{
DataAccess db = new DataAccess();
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
string id = Request.QueryString["id"].ToString();

if (Session["car"] != null)
{
Hashtable hash = Session["car"] as Hashtable;
if (!hash.ContainsKey(id))
{
hash.Add(id, 1);
}
else
{
hash[id] = int.Parse(hash[id].ToString()) + 1;