求高手解答代码问题

[gameover456]

运行程序图片不连续滚动,到最后一张停止,为什么????
<div id="demo" style="BACKGROUND:#214984;OVERFLOW:hidden;WIDTH:220px;COLOR:#ffffff;HEIGHT:144px">
<table align="left" cellpadding="0" cellspace="0" border="0">
<tr>
<td id="demo1" valign="top">
<asp:datalist id="dlYX" runat="server" RepeatColumns="10">
<ItemTemplate>
<a href=''><img src='<%#DataBinder.Eval(Container.DataItem,"imageUrl")%>' border="0" width="102" height="144"></a>
</ItemTemplate>
</asp:datalist></td>
<td id="demo2" valign="top"></td>
</tr>
</table>
</div>
<script>
var speed=30
demo2.innerHTML=demo1.innerHTML
function Marquee(){
if(demo2.offsetWidth-demo.scrollLeft<=0)
demo.scrollLeft-=demo1.offsetWidth
else{
demo.scrollLeft++
}
}
var MyMar=setInterval(Marquee,speed)
demo.onmouseover=function() {clearInterval(MyMar)}
demo.onmouseout=function() {MyMar=setInterval(Marquee,speed)}
</script>

[gameover456]

自己顶下

[mqc507]

.Sleeping()

[gameover456]

没人知道啊