<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<meta name="keywords" content="JS代码,悬浮漂浮,JS广告代码,JS特效代码" />
<meta name="description" content="此代码内容为弹性返回顶部JS代码，属于站长常用代码，更多悬浮漂浮代码请访问懒人图库JS代码频道。" />
<title>弹性返回顶部JS代码_懒人图库</title>
<SCRIPT type=text/javascript src="js/scrolltop.js"></SCRIPT>
<LINK rel=stylesheet type=text/css href="css/lrtk.css">
</head> <body style="text-align:center">
<div id="topcontrol" title="Scroll Back to Top" style="DISPLAY: none; position: fixed; bottom: 30px; left: 50%; margin-left: 491px; opacity: 1; cursor: pointer;">
<img src="http://www.paidai.com/images/new/top.jpg" style="width:53px; height:49px"/>
</div>
<SCRIPT type=text/javascript>goTopEx();</SCRIPT> <br /><br /><br /><br /><br /><br /><br />
<p>来源：<a href="http://www.thinkzm.com/" target="_blank">Redm赤美广告</a> 代码整理：<a href="http://www.lanrentuku.com/" target="_blank">懒人图库（西西）</a> 感谢：<a href="http://www.nifengla.com/" target="_blank">你疯啦</a></p>
<p>＊尊重他人劳动成果，转载请自觉注明出处！注：此代码仅供学习交流，请勿用于商业用途。</p>
<p></p>
<p><p>超出首屏范围，即会出现TOP按钮，否则自动隐藏。<br />
</p></p>
<p></p> </body>
</html>
// JavaScript Document
var goTopEx=function (){
var obj=document.getElementById("topcontrol");
function addEvent(obj,type,fn){
if(obj.attachEvent){
obj.attachEvent('on'+type,function(){
fn.call(obj);
})
}else{
obj.addEventListener(type,fn,false);
}
}
function getScrollTop(){
return document.documentElement.scrollTop||document.body.scrollTop;
}
function setScrollTop(value){
if(document.documentElement.scrollTop){
document.documentElement.scrollTop=value;
}else if(document.body.scrollTop){
document.body.scrollTop=value;
}
}
addEvent(window,'scroll',function(){
getScrollTop()>0?obj.style.display="":obj.style.display="none";
});
addEvent(obj,'click',function(){
var goTop=setInterval(scrollMove,10);
function scrollMove(){
setScrollTop(getScrollTop()/1.1);
if(getScrollTop()<1)clearInterval(goTop);
}
});
// window.onscroll=function(){getScrollTop()>0?obj.style.display="":obj.style.display="none";}
/*obj.onclick=function(){
var goTop=setInterval(scrollMove,10);
function scrollMove(){
setScrollTop(getScrollTop()/1.1);
if(getScrollTop()<1)clearInterval(goTop);
}
}*/
}
实现返回top功能，window.onscroll影响到前面滚动功能，使用事件处理addEvent添加事件处理，或用jquery的ready事件，$(window).ready(fn); ready事件可以同时注册多个，执行时，按照注册的先后顺序执行,可能还有其他办法，目前就知道这两种。