js 无间隙滚动函数

#speed ：速度 

#demo1：包含滚动内容的div

#demo2：空的div

#demo：最外层的div

function gundong(speed,demo1,demo2,demo) {

var speed_gd=speed var demo1=document.getElementById(demo1); var demo2=document.getElementById(demo2); var demo=document.getElementById(demo); demo2.innerHTML=demo1.innerHTML function Marquee(){ if(demo2.offsetTop-demo.scrollTop<=0) demo.scrollTop-=demo1.offsetHeight else{ demo.scrollTop++ } } var MyMar=setInterval(Marquee,speed_gd) demo.onmouseover=function() {clearInterval(MyMar)} demo.onmouseout=function() {MyMar=setInterval(Marquee,speed)} }