<DIV id="dd" contentEditable="true" >
<table border=1 id=Layer1><tr><td>fff
</td></tr></table>
<table border=1 id=Layer2><tr><td>dfdfd
</td></tr></table>
</DIV>
<table border=1 id=Layer1><tr><td>fff
</td></tr></table>
<table border=1 id=Layer2><tr><td>dfdfd
</td></tr></table>
</DIV>
<script>
var xx=0;
</script>
<table style="border:1px solid black;padding:0px;">
<tr>
<td id="oo" style="width:200px;height:400px;"></td>
<td style="cursor:move;position:absolute;left:200px;width:2px;height:400px;background-color:red;border:0px;"
ondragstart="setCapture();xx=event.x-this.offsetLeft;"
ondrag='this.style.left=event.x-xx;oo.style.width=this.style.left'
ondragend="releaseCapture();"></td>
</tr>
</table>
然后
document.execCommand('2D-Position','false','false');
自己试试,msdn上说的