请问大家这两段代码有什么区别？
代码一的鼠标移上去 this 指向当前对象。
但代码二的鼠标移上去 this 指向window。
请看这2个代码。。为什么会指向window啊。
self.startMove(this,{backgroundPositionX:-self.lang+this.offsetWidth});
startMove函数
我已经把startMove函数添加到Astyle对象的一个方法：this.startMove = startMove;为什么还会这样指向window ？
代码一：
<!doctype html><html> <head> </head> <body> <p id="para">para</p> <script type="text/javascript"> var $ = function(id){return typeof id == "string"?document.getElementById(id):id} function Person(name,age,job){ this.name = name; this.age = age; this.job = job; this.show = show; var self = this; this.start = start; $("para").onmouseover = function(){ self.start(this) } } function start(target){ console.log(target) } function show(){ console.log(this.name) } var obj = new Person("deepblue",28,"Web Engineer"); obj.show(); </script> </body> </html><!DOCTYPE HTML><html> <head> <title> New Document </title> <style type="text/css"> *{padding:0;margin:0;}.box{ float:left;}.box li{ list-style:none; height:24px;}.box a{ font-size:12px; color:#333;}.menuBox li{ list-style:none; height:24px; float:left; margin-right:5px;}.menuBox a{ font-size:12px; color:#333;}.menuBox a:hover{ color:#000;} </style> </head> <body> <div class="box"> <ul> <li><a href="#" class="ButtonStyle">·红十字总会今年财务收入近6亿</a></li> <li><a href="#" class="ButtonStyle">·中国南极科考队直升机失事 2名机组</a></li> <li><a href="#" class="ButtonStyle">·今年255人因食品安全案获刑 李克强要</a></li> <li><a href="#" class="ButtonStyle">·北京地税局证实年终奖多1元或多缴千元个税</a></li> <li><a href="#" class="ButtonStyle">·欧央行两个月内再次降息 宣布多项措施拯救欧洲</a></li> <li><a href="#" class="ButtonStyle">·时代周刊公布年度全球十大新闻：阿拉伯之春居首</a></li> <li><a href="#" class="ButtonStyle">·伊朗军方通过电视台播出击落美国无人机画面</a></li> <li><a href="#" class="ButtonStyle">·王晨会见ICANN总裁 政务微博：力行"织博为民"</a></li> <li><a href="#" class="ButtonStyle">·第五届中美互联网论坛举行 钱小芊发表演讲(图)</a></li> <li><a href="#" class="ButtonStyle">·高官全部落选工程院院士 个别单位领导曾拉票</a></li> <li><a href="#" class="ButtonStyle">·住建部官员：PM2.5指数升高与建造玻璃幕墙有关</a></li> </ul></div> <script type="text/javascript"> //var $ = function(id){return document.getElementById(id)} function Astyle(cName,seat){ this.cName = cName; this.seat = seat; this.elem = document.body; this.obj = getClass; this.lang = 1000; this.startMove = startMove; var self = this; for(var i=0; i<this.obj().length; i++){ this.obj()[i].style.textDecoration = "none"; this.obj()[i].style.background = "url(images/a_line.jpg) no-repeat "+(-this.lang)+"px "+this.seat; this.obj()[i].onmouseover = function(){ var tar =this; this.style.backgroundPosition = -this.lang*2 + "px"; if(this.style.backgroundPositionX != undefined){ //console.log(this) self.startMove(this,{backgroundPositionX:-self.lang+this.offsetWidth}); } } } } function startMove(target,object,onComplete){ console.log(target + ":" + this.cName) } function getClass(){ var aElem = this.elem.getElementsByTagName("*"); var aClass = []; var i=0; for(i=0; i<aElem.length; i++){ if(aElem[i].className == this.cName){ aClass.push(aElem[i]) } } return aClass; } var astyle = new Astyle("ButtonStyle","bottom"); astyle.obj() </script> </body></html>
var astyle = new Astyle("ButtonStyle","bottom");
astyle.obj()
</script>
</body>
</html>