<script type="text/javascript">
  
function add()
{
    var now = new Date();
  
    var div = document.getElementById('scrolldIV');
  
    div.innerHTML = div.innerHTML + 'time_' + now.getTime() + '<br />';
  
    div.scrollTop = div.scrollHeight;
}
  
function scrollWindow()
{
    scroll(0, 100000);
    setTimeout('scrollWindow()', 200);
}
  
window.onload = function() { scrollWindow(); } 
  
</script>

<div id="scrolldIV" style="overflow:scroll; height: 100px; width: 400px; border: 1px solid #999;">
</div>
  
<input type="button" value="插入一行" onclick="add();">