js实现图片无缝滚动

CSS：

<style type="text/css">
    #demo {
        background: #FFF;
        overflow:hidden;
        border: 1px dashed #CCC;
        width: 1000px;
        height:368px;
    }
    #demo img {
        border: 3px solid #F2F2F2;
    }
    #indemo {
        width: 8000%;
    }
    #demo1 , #demo2{
         float: left;
    }
</style>

HTML：

<div id="demo">
		<div id="indemo">
		    <div id="demo1">
			    <a href="#1"><img src="http://www.0351zhuangxiu.com/uploads/images/123.jpg" border="0" /></a>
			    <a href="#2"><img src="http://www.0351zhuangxiu.com/uploads/images/124.jpg" border="0" /></a>
			    <a href="#"><img src="http://www.0351zhuangxiu.com/uploads/images/125.jpg" border="0" /></a>
			    <a href="#"><img src="http://www.0351zhuangxiu.com/uploads/images/126.jpg" border="0" /></a>
			    <a href="#"><img src="http://www.0351zhuangxiu.com/uploads/images/127.jpg" border="0" /></a>
			    <a href="#"><img src="http://www.0351zhuangxiu.com/uploads/images/128.jpg" border="0" /></a>
		    </div>
		    <div id="demo2"></div>
        </div>
    </div>

JS向左滚动：

<script type="text/javascript">
        var speed=10;//控制速度
        var tab=document.getElementById("demo");
        var tab1=document.getElementById("demo1");
        var tab2=document.getElementById("demo2");
        tab2.innerHTML=tab1.innerHTML;
        function Marquee(){
            if(tab2.offsetWidth - tab.scrollLeft <= 0)
                tab.scrollLeft -=  tab1.offsetWidth;
            else{
                tab.scrollLeft++;
            }
            console.log("tab2.offsetWidth : " + tab2.offsetWidth + "tab.scrollLeft : " + tab.scrollLeft + "    tab2.offsetWidth - tab.scrollLeft = " + (tab2.offsetWidth - tab.scrollLeft));
        }        //定时器
        var MyMar=setInterval(Marquee,speed);
        //鼠标滑过停止滚动
        tab.onmouseover=function() {clearInterval(MyMar)};
        //鼠标滑出继续滚动
        tab.onmouseout=function() {MyMar=setInterval(Marquee,speed)};
    </script>

向上滚动：

CSS：

#indemo {
    height: 8000%;
}

function Marquee1(){
            if(tab2.offsetHeight - tab.scrollTop <= 0)
                tab.scrollTop -= tab1.offsetHeight;
            else{
                tab.scrollTop++;
            }
            console.log("tab2.offsetHeight : " + tab2.offsetHeight + "tab.scrollTop : " + tab.scrollTop + "    tab2.offsetHeight - tab.scrollTop = " + (tab2.offsetHeight - tab.scrollTop));
        }

向右滚动和向下滚动以此类推进行修改！