<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>ajax请求数据3</title>
</head>
<body>
<button id="btn">请求数据</button>
<h1 id="txt"></h1>
<script type="text/javascript">
var btn = document.getElementById(‘btn‘);
var txt = document.getElementById(‘txt‘);
btn.onclick = function() {
//1.创建XMLHttpRequest对象
var xhr = null;
if(window.XMLHttpRequest) {//非IE56
xhr = new XMLHttpRequest();//实例对象
}else {//IE56
xhr = new ActiveXObject(‘Microsoft.XMLHTTP‘);
}
//2.打开与服务器的链接
xhr.open(‘get‘,‘test3.php?_=‘ + new Date().getDate(),true);//生成不一样的url解决缓存问题
//3.发送给服务器
xhr.send(null);//get请求
//4.响应就绪
xhr.onreadystatechange = function() {
if (xhr.readyState == 4) {//请求完成
if(xhr.status == 200) {
var json = JSON.parse(xhr.responseText);
txt.innerHTML = json.sex;
}else {
alert(xhr.status);
}
}
}
}
</script>
</body>
</html>
<?php
$str = ‘{"name":"老王","sex":"男","age":"22","score":"58"}‘;
echo $str;
?>
原文：http://www.cnblogs.com/handsomehan/p/5865270.html