jqueryjsonajax二级联动菜单实例

<%@ WebHandler Language="C#" Class="Handler" %>
using System;
using System.Web;
using System.Data;
public class Handler : IHttpHandler
{
 Common coObj = new Common();
 public void ProcessRequest(HttpContext context)
 {
 if (context.Request.Params["n"] != null)
 {
 string num = context.Request.Params["n"].ToString();
 context.Response.ContentType = "text/plain";
 string str = "select * from address where a_num2=" + num;
 DataTable dt = coObj.GetTable(str);
 string json = JSONHelper.DataTableToJSON(dt);
 context.Response.Write(json);
 }
 }
 public bool IsReusable
 {
 get
 {
 return false;
 }
 }
}