ajax处理php返回json数据的实例代码

test.html

<label onclick="javascript:post_data();">click </label> 
function ajax_init() 
{ 
var ajax=false; 
try { 
ajax = new ActiveXObject("Msxml2.XMLHTTP"); 
} catch (e) { 
try { 
ajax = new ActiveXObject("Microsoft.XMLHTTP"); 
} catch (E) { 
ajax = false; 
} 
} 
if (!ajax && typeof XMLHttpRequest!='undefined') { 
ajax = new XMLHttpRequest(); 
} 
return ajax; 
} 
function post_data() 
{ 
var url = "/server/xml.php"; 
var show_check = document.getElementById("show_check"); 
var show_flag = document.getElementById("show_flag"); 
var ajax = ajax_init(); 
ajax.open("GET", url, true); 
//var img = "<img src='/img/loading.gif'>"; 
ajax.onreadystatechange = function() 
{ 
if (ajax.readyState == 4 && ajax.status == 200) 
{ 
var ret = ajax.responseText; 
var show_info = eval(ret); 
show_check.innerHTML = show_info[0].no1; // bsd 
show_flag.innerHTML = show_info[0].no2; // wuddy 
//alert("responseXML's value: " + info[0].firstChild.data); 
} 
/*else 
{ 
show.innerHTML = img; 
}*/ 
} 
ajax.send(null); 
}

json.php

<?php 
/* 这边如果写成 $info = array('no1'=>'bsd', 'no2'=>'wuddy', 'no3'=>'xie'); */ 
/* 同样要把html文件中必成 var show_info = eval('[' + ret + ']'); 都是返回一个对象 */ 
$info = array(array('no1'=>'bsd', 'no2'=>'wuddy', 'no3'=>'xie')); 
$userinfo = json_encode($info); 
echo $userinfo; 
?>