asp.net jquery

在asp.net中 我想用query是页面中的一个div内容刷新
请问有没有最简单的办法做到

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$("#div").load("test.aspx");

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http://topic.csdn.net/u/20100201/16/d6e5cab1-5b22-43c6-9f6b-e2700eb40ff5.html?73642 
在这.

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是这样的我做了一个关于验证码生成的页面image.aspx
后台代码是这样的：
C# code:

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.Drawing.Imaging;
using System.IO;
using System.Drawing;

public partial class Web_image : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
string tmp = RndNum(6);
HttpCookie a = new HttpCookie("ImageV",tmp);
Response.Cookies.Add(a);
this.ValidateCode(tmp);
}
private void ValidateCode(string VNum)
{
Bitmap Img=null;
Graphics g=null;
MemoryStream ms=null;

int gheight=VNum.Length*12;
Img=new Bitmap(gheight,25);
g=Graphics.fromImage(Img);
//背景颜色
g.Clear(Color.White);
//文字字体
Font f=new Font("Arial Black",10);
//文字颜色
SolidBrush s=new SolidBrush(Color.Black);
g.DrawString(VNum,f,s,3,3);
ms=ne