ASP.NET 2.0 中的无刷新页面

 这几天在微软网站看了一编客户端回客户端回调实现 (C#) 示例 
（网址为：http://msdn2.microsoft.com/zh-CN/library/ms178210.aspx）
用它就能实现基本Ajax的原System.Web.UI.ICallbackEventHandler理功能，而不学习一些Ajax框架的东西，感觉挺爽呀，可是运行起报错，后经过仔细查找原来是System.Web.UI.ICallbackEventHandler的接口不是它那样写的，可能它是原来的接口吧。后我照2.0的接口改成下面的样子，运行吗ok，是一个不错无刷新技术。
它的基本原理,微软的试例已经介绍非常祥细了，在此我就不搬门弄斧了，有兴趣的朋友去，去http://www.cnblogs.com/RicCC/archive/2006/09/10/500268.html这个网址看看吧

<% @ Page Language = " C# "  AutoEventWireup = " true "   CodeFile = " Default.aspx.cs "  Inherits = " _Default "   %>

<! DOCTYPE html PUBLIC  " -//W3C//DTD XHTML 1.0 Transitional//EN "   " http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd " >

< html xmlns = " http://www.w3.org/1999/xhtml " >
< head runat = " server " >
< title > 无标题页 </ title >
   < script type = " text/javascript " >
    function LookUpStock()
     {
        var lb = document.forms[0].ListBox1;
        var product = lb.options[lb.selectedIndex].text 
        CallServer(product, "");
    }
    
    function ReceiveServerData(rValue)
     {
        Results.innerText = rValue;
    }
   </ script >
</ head >
< body >
   < form id = " form1 "  runat = " server " >
     < div >
       < asp:ListBox ID = " ListBox1 "  Runat = " server " ></ asp:ListBox >
       < br  />
       < br  />
       < button onclick = " LookUpStock() " > Look Up Stock </ button >
       < br  />
       < br  />
      Items  in  stock:  < span ID = " Results " ></ span >
       < br  />
     </ div >
   </ form >
</ body >
</ html >

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;


public  partial  class  _Default : System.Web.UI.Page, System.Web.UI.ICallbackEventHandler
{
    protected System.Collections.Specialized.ListDictionary catalog;

    protected void Page_Load(object sender, EventArgs e)
    {
        String cbReference =
            Page.ClientScript.GetCallbackEventReference(this,
            "arg", "ReceiveServerData", "context");
        String callbackScript;
        callbackScript = "function CallServer(arg, context)" +
            "{ " + cbReference + "} ;";
        Page.ClientScript.RegisterClientScriptBlock(this.GetType(),
            "CallServer", callbackScript, true);

        catalog = new System.Collections.Specialized.ListDictionary();
        catalog.Add("monitor", 12);
        catalog.Add("laptop", 10);
        catalog.Add("keyboard", 23);
        catalog.Add("mouse", 17);

        ListBox1.DataSource = catalog;
        ListBox1.DataTextField = "key";
        ListBox1.DataBind();
    }

    String returnValue;
    public void RaiseCallbackEvent(String eventArgument)
    {
        
        if (catalog[eventArgument] == null)
        {
            returnValue = "-1";
        }
        else
        {
            returnValue = catalog[eventArgument].ToString();
        }
        //
    }

    public string GetCallbackResult()
    {
     return returnValue;
    }


}