代码如下：
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<link href="../css_all.css" rel="stylesheet" type="text/css">
<script>// Example: obj = findObj("image1");
function findObj(theObj, theDoc)
{
var p, i, foundObj;
if(!theDoc) theDoc = document;
if( (p = theObj.indexOf("?")) > 0 && parent.frames.length)
{
theDoc = parent.frames[theObj.substring(p+1)].document;
theObj = theObj.substring(0,p);
}
if(!(foundObj = theDoc[theObj]) && theDoc.all) foundObj = theDoc.all[theObj];
for (i=0; !foundObj && i < theDoc.forms.length; i++)
foundObj = theDoc.forms[i][theObj];
for(i=0; !foundObj && theDoc.layers && i < theDoc.layers.length; i++)
foundObj = findObj(theObj,theDoc.layers[i].document);
if(!foundObj && document.getElementById) foundObj = document.getElementById(theObj);
return foundObj;
}
</script>
<title>无标题文档</title>
<style type="text/css">
<!--
.emenu {
background-image: url(../img/3.gif);
background-repeat: no-repeat;
padding-left: 30px;
cursor: hand;
}
.submenu {
padding-left: 16px;
cursor: hand;
}
.file {
background-image: url(../img/point_03.gif);
background-repeat: no-repeat;
padding-left: 13px;
cursor: hand;
background-position: left top;
}
.mainmenu {
background-image: url(../img/4.gif);
background-repeat: no-repeat;
padding-left: 30px;
cursor: hand;
}
-->
</style>
</head>
<body>
<table width="166" border="0" cellspacing="0" cellpadding="0">
<tr><td width="166" height="15"></td>
</tr>
<tr valign="top">
<td height="20" class="emenu" onmouseup="with(findObj('Blueidea').style){display=display=='none'?'':'none';this.style.backgroundImage=display!='none'?'url(../img/1.gif)':'url(../img/3.gif)'}">机构职能</td>
</tr>
<tr id="Blueidea" style="display:none">
<td class="submenu" height="75"><table height="100%" border="0" cellspacing="0" cellpadding="0">
<tr valign="top">
<td height="19" class="file"><a href="#">司局领导</a></td>
</tr>
<tr valign="top">
<td height="22" class="file"><a href="01-2.html" target="change">主要职能</a></td>
</tr>
<tr valign="top">
<td height="28" valign="top" class="file"><a href="01.html" target="change">内设机构及联系<br/>
方式</a></td>
</tr>
</table></td>
</tr>
<tr valign="top">
<td height="20" class="emenu" onmouseup="with(findObj('zcfg').style){display=display=='none'?'':'none';this.style.backgroundImage=display!='none'?'url(../img/1.gif)':'url(../img/3.gif)'}">政策法规</td>
</tr>
<tr id="zcfg" style="display:none">
<td class="submenu" height="80"><table height="100%" border="0" cellspacing="0" cellpadding="0">
<tr valign="top">
<td class="file">国内法规</td>
</tr>
<tr valign="top">
<td class="file">国外法规</td>
</tr>
<tr valign="top">
<td class="file">国内政策</td>
</tr>
<tr valign="top">
<td class="file">国外政策</td>
</tr>
</table></td>
</tr>
<tr valign="top">
<td height="20" class="emenu" onmouseup="with(findObj('xggg').style){display=display=='none'?'':'none';this.style.backgroundImage=display!='none'?'url(../img/1.gif)':'url(../img/3.gif)'}">相关公告</td>
</tr>
<tr id="xggg" style="display:none">
<td class="submenu" height="80"><table height="100%" border="0" cellspacing="0" cellpadding="0">
<tr valign="top">
<td class="file">禁令公告</td>
</tr>
<tr valign="top">
<td class="file">警示通告</td>
</tr>
<tr valign="top">
<td class="file">动物疫情</td>
</tr>
<tr valign="top">
<td class="file">植物疫情</td>
</tr>
</table></td>
</tr>
<tr valign="top">
<td class="mainmenu" height="20">计划规划</td>
</tr>
<tr valign="top">
<td height="20" class="emenu" onmouseup="with(findObj('ywxx').style){display=display=='none'?'':'none';this.style.backgroundImage=display!='none'?'url(../img/1.gif)':'url(../img/3.gif)'}">业务信息</td>
</tr>
<tr id="ywxx" style="display:none">
<td class="submenu"><table border="0" cellpadding="0" cellspacing="0" valign="top">
<tr valign="top">
<td height="20" class="file"><a href="01dw/main.html" target="change">动物及其产品的检验<br/>检疫</a></td>
</tr>
<tr valign="top">
<td height="19" class="file"><a href="02sr/main.html" target="change">输入活动物的检疫</a></td>
</tr>
<tr valign="top">
<td height="30" class="file"><a href="03jj/main.html" target="change">进境动物遗传物质的<br/>检验检疫</a></td>
</tr>
<tr valign="top">
<td height="30" class="file"><a href="04jj/main.html" target="change">进境动物产品的检疫<br/>检疫</a></td>
</tr>
<tr valign="top">
<td height="20" class="file">出境活动物检验检疫</td>
</tr>
<tr valign="top">
<td height="26" class="file">出口动物产品检验检<br/>
疫</td>
</tr>
<tr valign="top">
<td height="21" class="file">生物制品检验检疫</td>
</tr>
<tr valign="top">
<td class="file">过境动物及其产品检<br/>验检疫</td>
</tr>
</table></td>
</tr>
</table>
</body>
</html>
请问我怎样修改能使这个树状菜单在页面打开时称展开状态？谢谢~~~！！！！
