新菜发帖！关于listbox控件的一些问题！

代码如下：
   这个是类文件：
using System;
using System.Collections;
using System.Data;
using System.Configuration;
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;


public class cart
{
    private ArrayList items;
    public cart()
    {
        items=new ArrayList();
    }
    //添加商品到购物车中
    public void additems(string item)
    {
        items.Add(item);
    }
    //从购物车中删除商品
    public void moveitems(string item)
    {
        items.Remove(item);
    }
    //查看购物车中的商品
    public ArrayList getitems()
    {
        return items;
    }
}
选书界面：
    using System;
using System.Data;
using System.Configuration;
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;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        string[] books = new string[] { "qw", "rt", "yu", "yu", "fg", "a", "sadf", "ghj", "fghgh" };
        this.ListBox1.DataSource = books;
        this.ListBox1.DataBind();
    }

    protected void Button1_Click(object sender, EventArgs e)
    {
        cart mycart;
        if (Session["cart"] == null)
        {
            mycart = new cart();
            Session["cart"] = mycart;
        }
        mycart = (cart)Session["cart"];
        //向购物车中增加书本
        mycart.additems(listbox1.selectItem.text);
        Session["cart"]=mycart;
    }
    protected void Button2_Click(object sender, EventArgs e)
    {
        Response.Redirect("Default2.aspx");
    }
}
购物车界面：
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class Default2 : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!this.IsPostBack)
        {
            cart mycart;
            if (Session["cart"] == null)
            {
                mycart = new cart();
                Session["cart"] = mycart;
            }
            else
            {
                mycart = (cart)Session["cart"];
                ListBox2.DataSource = mycart.getitems();
                ListBox2.DataBind();
            }
        }
      
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        cart mycart;
        if (Session["cart"] == null)
        {
            mycart = new cart();
            Session["cart"] = mycart;
        }
        else
        {
            mycart = (cart)Session["cart"];
            mycart.moveitems(listbox1.selectItem.Text);      
         
            ListBox2.DataSource = mycart.getitems();
            ListBox2.DataBind();
         
        }
    }
}
     今天又改了下，“listbox1.selectItem.Text”这个地方老是报错，如果用“listbox1.Items.ToString()”就可以实现功能，但是显示出来的却是“ System.Web.UI.WebControls”，listbox的属性不是很了解，望高手帮忙解决下，谢谢

[ 本帖最后由 搜寻者 于 2009-11-3 22:48 编辑 ]