js和htm做的树

javascript文件： 

指向：：<base target="main">
<script>function X(j){x='if('+j+'.style.display=="none"){'+j+'.style.display="";document.images.P'+j+'.src="img/line_0.gif";}else{'+j+'.style.display="none";document.images.P'+j+'.src="img/line_2.gif";}';eval(x);}</script>

例：HTM：：

  <tr height="20">
   <td class="td1">
    <img src="img/line_2.gif" align="absMiddle" onclick="X('OL')"
     ID="POL"><img src="img/online.gif" align="absMiddle"><a href="ViewOnline.aspx">在线名单</a>
   </td>
  </tr>
  <tr>
   <td class="td1">
    <table cellspacing="0" cellpadding="0" ID="OL" style="DISPLAY:none">
     <tr>
      <td class="td1">
       <ol>
        <li>
         <a href="ViewOnline.aspx">在线游客</a>
        <li>
         <a href="ViewOnline.aspx">在线会员</a></li></ol>
      </td>
     </tr>
    </table>
   </td>
  </tr>