请教如何实现LOADING

<table width="100%" border="0" cellspacing="0" cellpadding="0" height="100%">
  <tr> 
    <td align="center"><font color=gray>Loading...</font> 
      <form name=loading>
        <div align=center> 
          <p style="text-indent:0; word-spacing:0; margin:0">
            <input type=text name=chart size=46 style="font-family:Arial; font-weight:bolder; color:gray; 
background-color:white; padding:0px; border-style:none;">
            <br>
            <input type=text name=percent size=46 style="font-family:Arial; color:gray; text-align:center; 
border-width:medium; border-style:none;">
            <script>var bar = 0  
var line = "||" 
var amount ="||" 
count() 
function count(){ 
bar= bar+2 
amount =amount + line 
document.loading.chart.value=amount 
document.loading.percent.value=bar+"%" 
if (bar<99) 
{setTimeout("count()",50);} 
else 
{window.location = "http://www.xxiyy.com/";} 
}</script>
            </p>
        </div>
      </form>
    </td>
  </tr>
</table>