JQuery+ajax 三级联动
html中代码：
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title></title>
<script src="js/jquery-1.7.2.min.js"></script>
</head>
<body>
<select >
<option>加载中...</option>
</select>
<select >
<option>加载中...</option>
</select>
<select >
<option>加载中...</option>
</select>
<script type="text/javascript">
a($("#sel1"), "0001", "1");
$("#sel1").change(function () {
a($("#sel2"), $("#sel1").val(), "2");
});
$("#sel2").change(function () {
a($("#sel3"), $("#sel2").val(), "3");
});
function a(sel, code, count) {
$.ajax({
url: "ashxs/china.ashx",
data: { "code": code },
type: "post",
dataType: "json",
success: function (data) {
sel.empty();
for (i in data) {
sel.get(0).add(new Option(data[i].name, data[i].code));
}
if (count == "1") {
a($("#sel2"), $("#sel1").val(), "2");
}
if (count == "2") {
a($("#sel3"), $("#sel2").val(), "3");
}
}
});//ajax
}
</script>
</body>
</html>一般处理程序中的代码：
<%@ WebHandler Language="C#" Class="china" %>
using System;
using System.Web;
using System.Linq;
using System.Data.Linq;
using System.Collections;
using System.Collections.Generic;
public class china : IHttpHandler
{
DataClassesDataContext con = new DataClassesDataContext();
public void ProcessRequest(HttpContext context)
{
string end = "[";
int count = 0;
string code = context.Request["code"];
List<ChinaStates> list = con.ChinaStates.Where(r => r.ParentAreaCode == code).ToList();
if (list.Count > 0)
{
foreach (ChinaStates c in list)
{
if (count <= 0)
{
end += "{\"name\":\"" + c.AreaName + "\",\"code\":\"" + c.AreaCode + "\"}";
}
else
{
end += ",{\"name\":\"" + c.AreaName + "\",\"code\":\"" + c.AreaCode + "\"}";
}
count++;
}
}
end += "]";
context.Response.Write(end);
}
public bool IsReusable
{
get
{
return false;
}
}
}