ajaxTest3.jsp的页面：
<%@ 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="/go.html?url=<%=basePath%>">
<title>My JSP 'ajax1.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">
<script type="text/javascript">
//定义XMLHttpRequest对象
function jsAjaxPost(){
if(window.XMLHttpRequest){
var xmlhttprequest = new XMLHttpRequest();
xmlhttprequest.open('POST','./servlet/ajaxTest3');//请求方式
xmlhttprequest.setRequestHeader("Content-Type","application/x-www-form-urlencoded");//请求头
xmlhttprequest.onreadystatechange=function (){
if(xmlhttprequest.readyState===4&&xmlhttprequest.status===200){
//alert("rh--"+xmlhttprequest.getResponseHeader("Content-Type"));
var type=xmlhttprequest.getResponseHeader("Content-Type");//响应头包含json是json响应
if(type.indexOf("json")!=-1){
var ul = document.getElementById("jsajaxpost");
ul.innerHTML += "<li>status:" + xmlhttprequest.status + "</li>";
var xmlDoc=xmlhttprequest.responseText;
//alert("1---"+xmlDoc);
var data=eval(xmlDoc);
//因为用data instanceof Array得到的是false，但可以当数组用
//所以认为eval将json格式的string值转成类数组对象
// alert(data);
// alert(data.length);
// alert("1---"+typeof(data));
// alert("2---"+data instanceof Array);
ul.innerHTML += "<li>return:" +"userName:"+data[0].userName + "userId:"+data[0].userId+"</li>";
ul.innerHTML += "<li>return:" +"userName:"+data[1].userName + "userId:"+data[1].userId+ "</li>";
}
}
};
xmlhttprequest.send("user=我1&com=a2");
}
}
</script>
</head>
<body>
<ul>
<li>
<a href="/go.html?url=javascript:jsAjaxPost();">(POST)javascript ajax testing.</a>
<ul id="jsajaxpost"></ul>
</li>
</ul>
</body>
</html>
<%@ page language="java"
