1、因为你的按钮和框不在一个层 确保它们在一个层就行了
2、js解决 在展开和收缩子菜单的js中 获得整个菜单框的高度 然后赋值给 按钮层的top
要代码的话 自己先把代码贴出来
<html><head>
<meta http-equiv="Content-Type" content="text/htmlcharset=gb2312">
<meta name="keywords" content="">
<style type=text/css>
table { border:0px}
td { font:normal 12px 宋体}
img { vertical-align:bottomborder:0px}
a { font:normal 12px 宋体color:#215DC6text-decoration:none}
a:hover { color:#428EFF }
/*
展开层的样式
**/
.sec_menu { border-left:1px solid #000000border-right:1px solid whiteborder-bottom:1px solid whiteoverflow:hiddenbackground:#D6DFF7}
/*
根节点字体样式控制
**/
.menu_title span { position:relativetop:2pxleft:8pxcolor:#215DC6font-weight:bold}
.menu_title2 span { position:relativetop:2pxleft:8pxcolor:#428EFFfont-weight:bold}
</style>
<script language=javascript>
function menuShow(obj,maxh,obj2)
{
if(obj.style.pixelHeight<maxh)
{
obj.style.pixelHeight+=maxh/20
obj.filters.alpha.opacity+=5
obj2.background="image/menudown.gif"
if(obj.style.pixelHeight==maxh/10)
obj.style.display='block'
myObj=obj
myMaxh=maxh
myObj2=obj2
setTimeout('menuShow(myObj,myMaxh,myObj2)','5')
}
}
function menuHide(obj,maxh,obj2)
{
if(obj.style.pixelHeight>0)
{
if(obj.style.pixelHeight==maxh/20)
obj.style.display='none'
obj.style.pixelHeight-=maxh/20
obj.filters.alpha.opacity-=5
obj2.background="image/menuup.gif"
myObj=obj
myMaxh=maxh
myObj2=obj2
setTimeout('menuHide(myObj,myMaxh,myObj2)','5')
}
else
if(whichContinue)
whichContinue.click()
}
function menuChange(obj,maxh,obj2)
{
if(obj.style.pixelHeight)
{
menuHide(obj,maxh,obj2)
whichOpen=''
whichcontinue=''
}
else
if(whichOpen)
{
whichContinue=obj2
whichOpen.click()
}
else
{
menuShow(obj,maxh,obj2)
whichOpen=obj2
whichContinue=''
}
}
</script>
<base target=main>
</head>
<body onselectstart="return false" ondragstart="return false" oncontextmenu="return false">
<table width=158 border="0" align=center cellpadding=0 cellspacing=0>
<tr style="cursor:hand">
<td height=25 background=image/menudown.gif class=menu_title id=menuTitle1 onClick="menuChange(menu1,80,menuTitle1)" onmouseover=this.className='menu_title2'onmouseout=this.className='menu_title'>
<span>系统选项</span>
</td>
</tr>
<tr>
<td>
<div class=sec_menu style="width:158pxheight:80pxfilter:alpha(Opacity=100)overflow:hidden" id=menu1>
<table cellpadding=0 cellspacing=0 align=center width=135 style="position:relativetop:10px">
<tr>
<td height=20>
<img src="image/nofollow.gif" width="15" height="15"><a href=../../3our.com/index.html onfocus=this.blur()>安全选项</a>
</td>
</tr>
<tr>
<td height=20>
<img src="image/nofollow.gif" width="15" height="15"><a href=../../3our.com/index.html onfocus=this.blur()>垃圾邮件选项</a>
</td>
</tr>
<tr>
<td height=20>
<img src="image/nofollow.gif" width="15" height="15"><a href=../../3our.com/index.html onfocus=this.blur()>
动态规则选项</a>
</td>
</tr>
</table>
</div>
</td>
</tr>
</table>
<script language=javascript>
var whichOpen=menuTitle1
var whichContinue=''
</script>
<table width=158 border="0" align=center cellpadding=0 cellspacing=0>
<tr style="cursor:hand">
<td height=25 background=image/menuup.gif class=menu_title id=menuTitle2 onClick="menuChange(menu2,120,menuTitle2)" onmouseover=this.className='menu_title2'onmouseout=this.className='menu_title'>
<span>系统规则</span>
</td>
</tr>
<tr>
<td>
<div class=sec_menu style="width:158height:0filter:alpha(Opacity=0)display:none" id=menu2>
<table cellpadding=0 cellspacing=0 align=center width=135 style="position:relativetop:10px">
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
IP过滤规则</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
信封过滤规则</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
信头过滤规则</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
信体过滤规则</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
附件过滤规则</a>
</td>
</tr>
</table>
</div>
</td>
</tr>
</table>
<table width=158 border="0" align=center cellpadding=0 cellspacing=0>
<tr style="cursor:hand">
<td height=25 background=image/menuup.gif class=menu_title id=menuTitle3 onClick="menuChange(menu3,120,menuTitle3)" onmouseover=this.className='menu_title2'onmouseout=this.className='menu_title'>
<span>系统管理</span>
</td>
</tr>
<tr>
<td>
<div class=sec_menu style="width:158height:0filter:alpha(Opacity=0)display:none" id=menu3>
<table cellpadding=0 cellspacing=0 align=center width=135 style="position:relativetop:10px">
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
用户管理</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
进程管理</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
主机运行状态</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
数据备份</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
垃圾目录管理</a>
</td>
</tr>
</table>
</div>
</td>
</tr>
</table>
<table width=158 border="0" align=center cellpadding=0 cellspacing=0>
<tr style="cursor:hand">
<td height=25 background=image/menuup.gif class=menu_title id=menuTitle4 onClick="menuChange(menu4,140,menuTitle4)" onmouseover=this.className='menu_title2'onmouseout=this.className='menu_title'>
<span>系统统计</span>
</td>
</tr>
<tr>
<td>
<div class=sec_menu style="width:158height:0filter:alpha(Opacity=0)display:none" id=menu4>
<table cellpadding=0 cellspacing=0 align=center width=135 style="position:relativetop:10px">
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
IP过滤统计</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
信封过滤统计</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
信头过滤统计</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
信体过滤统计</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
附件过滤统计</a>
</td>
</tr>
<tr>
<td height=20>
<img src=image/nofollow.gif><a href=../../3our.com/index.html onfocus=this.blur()>
动态规则统计</a>
</td>
</tr>
</table>
</div>
</td>
</tr>
</table>
</body>
</html>