ajax可以返回文本类型数据和xml类型数据，xml是计算机通用语言 可以使用js解析返回xml类型数据的dom对象
前端页面
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="Generator" content="EditPlus®">
<meta name="Author" content="">
<meta name="Keywords" content="">
<meta name="Description" content="">
<title>Ajax</title>
<script type="text/javascript">
function createXHR(){
var xhr=null;
if(window.XMLHttpRequest){
xhr=new XMLHttpRequest();
}else if(window.ActiveXObject){
xhr=new ActiveXObject('Microsoft.XMLHttp');
}
return xhr;
}
function returnxml(){
var xhr=createXHR();
xhr.open('GET','./returnxml.php',true);
xhr.onreadystatechange=function (){
if(this.readyState==4&&this.status==200){
//alert(this.responseXML);//[object XMLDocument]
var xmldom=this.responseXML;
var title=xmldom.getElementsByTagName('title')[0];
var title=title.firstChild.wholeText;
var str='书名:'+title+'<br/>';
var price=xmldom.getElementsByTagName('price')[0].firstChild.wholeText;
var desc=xmldom.getElementsByTagName('desc')[0].firstChild.wholeText;
str=str+'价格:'+price+'<br/>';
str=str+'详细信息：'+desc+'<br/>';
str=str+'状态码：'+this.status+'<br/>';
str=str+'状态文字：'+this.statusText+'<br/>';
str=str+'返回值类型：'+this.getResponseHeader('content-type')+'<br/>';
str=str+'返回值长度：'+this.getResponseHeader('content-length')+'<br/>';
str=str+'ip：'+this.getResponseHeader('x-forwarded-for')+'<br/>';
document.getElementById('book').innerHTML=str;
}
}
xhr.send(null);
}
</script>
</head>
<body>
<input type="button" value="返回值xml" onclick="returnxml();"/>
<div id="book"></div>
</body>
</html>
returnxml.php
<?php
header('content-type:text/xml');
?>
<?xml version="1.0" encoding="utf8" ?>
<bookstore><book><title>ajax详解</title><price>39.9元</price><desc>学习ajax的最强帮</desc></book></bookstore>
结果显示效果
