<!DOCTYPE HTML> <html> <head> <meta charset="utf-8"> <title>无标题文档</title> <script src="new_ajax.js"></script> <script> window.onload=function () { var oBtn=document.getElementById('btn1'); oBtn.onclick=function () { ajax('a.txt', function (str){ alert(str); }); }; }; </script> </head> <body> <input id="btn1" type="button" value="读取" /> </body> </html>
一下是引入的封装好的new_ajax.js
function ajax(url, fnSucc, fnFaild) { //1.创建Ajax对象 if(window.XMLHttpRequest) //低版本IE6浏览器 { var oAjax=new XMLHttpRequest(); } else { var oAjax=new ActiveXObject("Microsoft.XMLHTTP"); } //2.连接服务器 //open(方法, 文件名, 异步传输) oAjax.open('GET', url, true); //3.发送请求 oAjax.send(); //4.接收返回 oAjax.onreadystatechange=function () { //oAjax.readyState //浏览器和服务器，进行到哪一步了 if(oAjax.readyState==4) //读取完成 { if(oAjax.status==200) //成功 { fnSucc(oAjax.responseText); } else { if(fnFaild) { fnFaild(oAjax.status); } //alert('失败:'+oAjax.status); } } }; }