<!doctype html> <html> <head> <meta charset="utf-8"> <title>无标题文档</title> <style> #div1 {width:100px; height:150px; background:red; position:absolute; right:0; bottom:0;} </style> <script> window.onscroll=function() { var oDiv=document.getElementById('div1'); var scrollTop=document.documentElement.scrollTop||document.body.scrollTop; oDiv.style.top=document.documentElement.clientHeight-oDiv.offsetHeight+scrollTop+'px'; } var timer=null; function startMove(iTarget) { var oDiv=document.getElementById('div1'); clearInterval(timer); timer=setInterval(function() { var speed={iTarget-oDiv.offsetTop}/8; speed=speed>0?Math.ceil(speed):Math.floor(speed); if(oDiv.offsetHeight==iTarget) { clearInterval(timer); } else { oDiv.style.Top=oDiv.offsetTop+speed+'px'; } },30); } </script> </head> <body style="height:2000px;"> <div id="div1"></div> </body> </html>