-------select.jsp------------------------------------------------------------------------------------------------------------------------------------------
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
<script type="text/javascript" src="js/jquery-3.1.0.min.js"></script>
</head>
<body>
<select id="s1" onchange="jquery_send()">
<option value="cd">成都</option>
<option value="cq">重庆</option>
</select>
<select id="s2">
</select>
</body>
<script type="text/javascript">
//方式一.json------------------------------------------------------------------------------------------------
//创建XMLHttpRequest对象
/*function createXMLHttpRequest(){
var XMLHttp;
try{
//大多数浏览器,以及IE7和IE更高版本
XMLHttp = new XMLHttpRequest();
}catch(e){
try{
//IE5.5及以下的版本
XMLHttp = new ActiveXObject("Microsoft.XMLHTTP");
}catch(e){
try{
//IE6.0
XMLHttp = new ActiveXObject("Msxml2.XMLHTTP");
}catch(e){
//以上都不是,执行的代码
}
}
}
return XMLHttp;
}
function send(){
var s1 = document.getElementById("s1").value;
var XMLHttp = createXMLHttpRequest();
//1.打开服务器的连接
XMLHttp.open("post","json.do?optionName="+s1, true);
XMLHttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
//2.发送请求
XMLHttp.send(null);
//3.接收服务器响应
XMLHttp.onreadystatechange = function(){
//4.表示服务器响应结束,200表示服务器成功响应
if(XMLHttp.readyState == 4 && XMLHttp.status == 200){
var xy = XMLHttp.responseText;
var xy_obj = eval("("+xy+")"); //把后台传过来的json字符串,转换成js类型
$("#s2").empty();
for(var i=0; i<xy_obj.length; i++){
$("#s2").append("<option value='"+xy_obj[i].option_value+"'>"+xy_obj[i].option_name+"</option>");
}
}
}
}
$(function(){
send();
})*/
//方式二.jquery的ajax函数--------------------------------------------------------------------------------------------------
function jquery_send(){
$.ajax({
type:"post",
url:"json.do?optionName="+$("#s1").val(),
dataType:"json",
success:function(data){
$("#s2").empty();
$.each(data,function(i,obj){
$("#s2").append("<option value='"+obj.option_value+"'>"+obj.option_name+"</option>");
});
}
})
}
$(function(){
jquery_send();
})
</script>
</html>