var xhr = new XMLHttpRequest();
function t1(){
xhr.open('post','a3.PHP');
xhr.setRequestHeader('content-type','application/x-www-form-urlencoded'); //post 必写
xhr.onreadystatechange = function (){
if(xhr.readyState == 4){
var obj = eval('(' + xhr.responseText + ')') //把字符串转成了JS对象~~
alert(obj.username) //直接读取对象属性~
}
}
xhr.send(null); //有没有数据都要send()
}
</script>
</head>
<body>
<input type="button" value="接收json格式" onclick="t1();" />
