来个例子：(json.html)
<html lang="en"> <head> <meta charset="UTF-8"> <title>Document</title> <script src="js/jquery.js"></script> </head> <body> <input type="button" value="submit" id="submit"> <div id="txt">&</div> <script> //监听对象 document.getElementById('submit').onclick = function(){ post("json.php","name=复读机1&age=123",function(data){ console.log(data); },"json") } //简单的post封装 function post(url,data,callback,dataType){ var xhr = new XMLHttpRequest(); xhr.onreadystatechange = function(){ if(xhr.readyState == 4){ callback(JSON.parse(xhr.responseText)); } } xhr.open("post",url,true); xhr.setRequestHeader("Content-Type","application/x-www-form-urlencoded") xhr.send(data); } </script> </body> </html>
json.php
<?php $info = array("name"=>"复读机2","age"=>223); $infoencode = json_encode($info);//转化为json格式 echo $infoencode; ?>
如果php文件是gb2312格式,把变量值转化为utf-8格式的，因为json_encode函数的参数必须是utf-8：
<?php $info = array("name"=>"复读机2","age"=>223); foreach($info as $name => $value){ $infogb["$name"] = iconv('gb2312','utf-8',$value); } $infoencode = json_encode($infogb); echo $infoencode; ?>
总结一下：前端向后端请求发送的数据还是查询字符串格式，而后端向前端响应的数据为json格式以便于用javascript解析。