绑定在datalist中图片如何实现不间断左右滚动

<DIV id="demo" style="OVERFLOW: hidden; WIDTH: 100%; COLOR: #ffffff">
<TABLE cellSpacing="0" cellPadding="0" align="left" border="0" cellspace="0">
<TBODY>
<TR>
<TD id="demo1" vAlign="top">
<asp:DataList id="DataList1" runat="server" RepeatDirection="Horizontal" Width="464px">
<ItemTemplate>
<div align="center">
<%# DataBinder.Eval(Container.DataItem,"uname")%>
</div>
</ItemTemplate>
</asp:DataList>
</TD>
<TD id="demo2" vAlign="top">
</TD>
</TR>
</TBODY>
</TABLE>
</DIV>
<SCRIPT>
var speed3=25//速度数值越大速度越慢
demo2.innerHTML=demo1.innerHTML
function Marquee()...{
if(demo2.offsetWidth-demo.scrollLeft<=0)
demo.scrollLeft-=demo1.offsetWidth
else{
demo.scrollLeft++
}
}
var MyMar=setInterval(Marquee,speed3)
demo.onmouseover=function() ...{clearInterval(MyMar)}
demo.onmouseout=function() ...{MyMar=setInterval(Marquee,speed3)}
</SCRIPT>