index.jsp
1 <%@ page language="java" contentType="text/html; charset=UTF-8"
2 pageEncoding="UTF-8"%>
3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
4 <html>
5 <head>
6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
7 <title>Insert title here</title>
8 <script type="text/javascript">
9 window.onload=function(){
10 //1.获取a节点,并对其添加onclick响就函数
11 document.getElementsByTagName("a")[0].onclick=function(){
12 //3.创建一个XMLHttpRequest对象
13 var request=new XMLHttpRequest();
14 //4.准备发送请求的数url,加上时间戳
15 var url=this.href +"?time=" + new Date();
16 var method="GET";
17 //5.调用XMLHttpRequest的open方法
18 request.open(method,url);
19 //6.调用XMLHttpRequest的send方法
20 request.send(null);
21 //7.为XMLHttpRequest对象添加onreadystatechange响应函数
22 request.onreadystatechange = function(){
23 //8.判断响应是否完成:XMLHttpRequest对象的readyState属性为4的时侯
24 if(request.readyState == 4){
25 //9.再判断响应是否可用:XMLHttpRequest对象status属性值为200
26 if(request.status == 200||request.status == 304){
27 //10.打印响 应结果:reponseText
28 alert("aaa")
29 alert(request.responseText);
30 }
31 }
32 }
33 //2.取消a节点默认行为
34 return false;
35 }
36 }
37 </script>
38 </head>
39 <body>
40 <a href="test.txt">test helloWord!</a>
41 </body>
42 </html>
test.txt
hello world,the first ajax!