lastScrollY=0;//固定层top值function heartBeat(){var diffY;//网页被卷起来的高度if (document.documentElement && document.documentElement.scrollTop){//判定是否直接document.documentElement或者被被卷起的值(ie)diffY = document.documentElement.scrollTop;}else if (document.body){//火狐diffY = document.body.scrollTop;}else{/*Netscape stuff*/}//alert(diffY);percent=.1*(diffY-lastScrollY);if(percent>0)percent=Math.ceil(percent);else percent=Math.floor(percent);document.getElementById("zixunss").style.top=parseInt(document.getElementById("zixunss").style.top)+percent+"px";lastScrollY=lastScrollY+percent;//alert(lastScrollY);}window.setInterval("heartBeat()",1)