<!-- 异步函数 setTimeout readFile writeFile readdir ajax -->

<script> function get(url,callback) { var oReq = new XMLHttpRequest() //当请求加载成功之后要调用指定的函数 oReq.onload = function () { //我现在需要得到这里的 oReq.responseText callback(oReq.responseText) } oReq.open("get",url,true) oReq.send() } get(‘data.json‘,function (data) { console.log(data) }) </script>