// JavaScript Document

var speed=10;
var direction="left";
document.getElementById("demo2").innerHTML=document.getElementById("demo1").innerHTML	;//克隆demo1为demo2
function Marquee(){
if(document.getElementById("demo2").offsetWidth-document.getElementById("demo").scrollLeft<=0)	//当滚动至demo1与demo2交界时
document.getElementById("demo").scrollLeft-=document.getElementById("demo1").offsetWidth;		//demo跳到最顶端
else{
	if(direction=="left")
	{
document.getElementById("demo").scrollLeft+=2;
	}
	else
	{
		if(document.getElementById("demo").scrollLeft>0)
		{
	document.getElementById("demo").scrollLeft-=2;
		}
		}

}
}
var MyMar=setInterval(Marquee,speed);	//设置定时器
document.getElementById("demo").onmouseover=function() {clearInterval(MyMar);};//鼠标移上时清除定时器达到滚动停止的目的
document.getElementById("demo").onmouseout=function() {MyMar=setInterval(Marquee,speed)};//鼠标移开时重设定时器


function toleft()
{
	direction="left";
	
	}
	function toright()
{
	direction="right";
	
	}