<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm2.aspx.cs" Inherits="JqueryDemoTest.WebForm2" %>
<!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></title>
<script src="js/jquery-1.4.1.min.js" type="text/javascript"></script>
<script src="js/jquery-1.4.1-vsdoc.js" type="text/javascript"></script>
<script type="text/javascript">
$(function () {
$('#btn').click(function () {
$.post('Handler.ashx', { val: $("#<%=ddlMain.ClientID %>").val() }, function (data) {
var json = eval(data);
var html = '';
for (var i in json) {
html += '<option value="' + json[i].Value + '">' + json[i].Name + '</option>';
}
$("#<%=ddlSub.ClientID %>")[0].options.length = 0;
$(html).appendTo($("#<%=ddlSub.ClientID %>"));
});
});
});
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:DropDownList ID="ddlMain" runat="server">
<asp:ListItem Text="一级城市" Value="1"></asp:ListItem>
<asp:ListItem Text="旅游城市" Value="2"></asp:ListItem>
</asp:DropDownList>
<asp:DropDownList ID="ddlSub" runat="server">
</asp:DropDownList>
<input type="button" id='btn' value='click me' />
</div>
</form>
</body>
</html>
code ashx
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace JqueryDemoTest
{
/// <summary>
/// Summary description for Handler
/// </summary>
public class Handler : IHttpHandler
{
public void ProcessRequest(HttpContext context)
{
context.Response.ContentType = "text/plain";
string json = string.Empty;
if (context.Request.Form["val"] == "1")
{
json = "[{\"Name\":\"北京\",\"Value\":1},{\"Name\":\"深圳\",\"Value\":2},{\"Name\":\"上海\",\"Value\":3}]";
}
else if (context.Request.Form["val"] == "2")
{
json = "[{\"Name\":\"杭州\",\"Value\":4},{\"Name\":\"苏州\",\"Value\":5},{\"Name\":\"桂林\",\"Value\":6}]";
}
context.Response.Write(json);
context.Response.End();
}
public bool IsReusable
{
get
{
return false;
}
}
}
}
