用纯XMLHttpRequest实现AJAX 

 1 <!DOCTYPE html>
 2 <html xmlns="http://www.w3.org/1999/xhtml">
 3 <head>
 4     <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 5     <title></title>
 6     <script type="text/javascript">
 7         /**
 8         *创建XMLHttpRequest对象
 9         */
10         function createXhr() {
11             var xhr = null;
12             if (window.XMLHttpRequest) {
13                 xhr = new XMLHttpRequest();
14             }
15             else {
16                 xhr = new ActiveXObject("Microsoft.XMLHttp");
17             }
18             return xhr;
19         }
20 
21         function testXHR() {
22             var xhr = createXhr();
23             window.alert(xhr);
24         }
25 
26         function getServerTest() {
27             //获取xhr对象
28             var xhr = createXhr();
29             //创建请求
30             xhr.open("get", "ajax.ashx", true);
31             //设置回调函数
32             xhr.onreadystatechange = function () {
33                 if (xhr.readyState == 4 && xhr.status == 200) {
34                     //服务器已正常处理请求 并正确响应数据到客户端
35                     var resText = xhr.responseText;
36                     document.getElementById("hh").innerText = resText;
37                 }
38             }
39             //4.发送请求
40             xhr.send(null);
41         }
42     </script>
43 </head>
44 <body>
45     <input type="button" value="Test Xhr" onclick="testXHR()">
46     <h2 id="hh"></h2>
47     <a href="javascript:getServerTest()">提交数据</a>
48 </body>
49 </html>

 

posted @ 2017-08-13 11:32  Rohmeng  阅读(145)  评论(0)    收藏  举报