可以展开刷新不改变的二级树形菜单，大类点击不展开小类，小类有旁边的图标展开（图）

以展开刷新不改变的二级树形菜单，大类点击不展开小类，小类有旁边的图标展开。

<!--#include file="conn.asp"-->
<SCRIPT language=JavaScript> 
    var __cc_uid="shenglu"; 
</SCRIPT>
<SCRIPT type=text/javascript>
var persistmenu="yes" //"yes" or "no". Make sure each SPAN content contains an incrementing ID starting at 1 (id="sub1", id="sub2", etc)
var persisttype="sitewide" //enter "sitewide" for menu to persist across site, "local" for this page only

if (document.getElementById){ //DynamicDrive.com change
document.write('<style type="text/css">/n')
document.write('.submenu{display: none;}/n')
document.write('</style>/n')
}

function SwitchMenu(obj){
        if(document.getElementById){
        var el = document.getElementById(obj);
        var ar = document.getElementById("masterdiv").getElementsByTagName("tr"); //DynamicDrive.com change
                if(el.style.display != "block"){ //DynamicDrive.com change
                        for (var i=0; i<ar.length; i++){
                                if (ar[i].className=="submenu") //DynamicDrive.com change
                                ar[i].style.display = "none";
                        }
                        el.style.display = "block";
                }else{
                        el.style.display = "none";
                }
        }
}

function get_cookie(Name) { 
var search = Name + "="
var returnvalue = "";
if (document.cookie.length > 0) {
offset = document.cookie.indexOf(search)
if (offset != -1) { 
offset += search.length
end = document.cookie.indexOf(";", offset);
if (end == -1) end = document.cookie.length;
returnvalue=unescape(document.cookie.substring(offset, end))
}
}
return returnvalue;
}

function onloadfunction(){
if (persistmenu=="yes"){
var cookiename=(persisttype=="sitewide")? "switchmenu" : window.location.pathname
var cookievalue=get_cookie(cookiename)
if (cookievalue!="")
document.getElementById(cookievalue).style.display="block"
}
}

function savemenustate(){
var inc=1, blockid=""
while (document.getElementById("sub"+inc)){
if (document.getElementById("sub"+inc).style.display=="block"){
blockid="sub"+inc
break
}
inc++
}
var cookiename=(persisttype=="sitewide")? "switchmenu" : window.location.pathname
var cookievalue=(persisttype=="sitewide")? blockid+";path=/" : blockid
document.cookie=cookiename+"="+cookievalue
}

if (window.addEventListener)
window.addEventListener("load", onloadfunction, false)
else if (window.attachEvent)
window.attachEvent("onload", onloadfunction)
else if (document.getElementById)
window.onload=onloadfunction

if (persistmenu=="yes" && document.getElementById)
window.onunload=savemenustate

</SCRIPT>


<STYLE type=text/css>.menutitle {
PADDING-RIGHT: 1px; PADDING-LEFT: 1px; MARGIN-BOTTOM: 1px; PADDING-BOTTOM: 1px; MARGIN-LEFT: auto; WIDTH: 200px; CURSOR: pointer; COLOR: #000000; MARGIN-RIGHT: auto; font-size:12px;font-weight:bold;
}
.submenu {
        MARGIN-BOTTOM: 0.5em
}
</STYLE>

<table width="200" border="0" cellspacing="0" cellpadding="0" align="left">

                 <Tr><td class="catalog" align="center" bgcolor="#666666" height="25">Product Catalog</td></Tr>
              <tr> 
                <td> 
                 <!--菜单开始--><TABLE id=masterdiv cellSpacing=0 cellPadding=0 width="100%" align=center border=0>
              <TBODY>
                          
                          <%
                set rsBigClass1=server.CreateObject("adodb.recordset")
rsBigClass1.open "Select * From type1",conn,1,1
    j=0
        do while not rsBigClass1.eof
        bigclassname=rsbigclass1("bigclassname")
        sanjib=bigclassname
        if inStr(sanjib," ")>0 then '判断是否含有“ ”字符
        sanjib=replace(sanjib," ","-")  '替换“ ”字符为“-”
        end if
        j=j+1
        
%>
              <TR class=menutitle>
                <TD height="20">&nbsp;&nbsp;&nbsp;&nbsp;<a href="product_<%=sanjib%>__page_1.htm" class="leftmenu"><%=rsBigClass1("BigClassName")%></a>
                </TD><Td valign="middle"  onClick="SwitchMenu('sub<%=j%>')"><a href="#" onClick="javascript:showtable<%="a"&i%>();"><%set rscheck=server.CreateObject("adodb.recordset")
          rscheck.open "Select * From type2 Where bigclassid=" & rsBigClass1("bigclassid"),conn,1,1
          if not(rscheck.bof and rscheck.eof) then%><img src=image/nvdown.jpg border="0"><%end if%></a></td></TR>
                                
                                   <TR class=submenu id=sub<%=j%>>
                <TD colspan="2">
                                
                                
                                
                  <TABLE cellSpacing=0 cellPadding=0 width="100%" border=0>
                                  
                    <TBODY>
                                        <%
          set rsSmallClass1=server.CreateObject("adodb.recordset")
          rsSmallClass1.open "Select * From type2 Where bigclassid=" & rsBigClass1("bigclassid"),conn,1,1
          if not(rsSmallClass1.bof and rsSmallClass1.eof) then
                do while not rsSmallClass1.eof
                smallclassname=rssmallclass1("smallclassname")
                sanjis=smallclassname
                if inStr(sanjis," ")>0 then '判断是否含有“ ”字符
                sanjis=replace(sanjis," ","-")  '替换“ ”字符为“-”
                end if
        %>        
                                        <tr><Td><a href="product_<%=sanjib%>_<%=sanjis%>_page_1.htm" class="leftmenu">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<%=rsSmallClass1("SmallClassName")%></a></Td></tr>
                                        <%
                        rsSmallClass1.movenext
                loop
          end if
          rsSmallClass1.close
          set rsSmallClass1=nothing        %>
                                        </TBODY></TABLE>
                                        </TD></TR>
                                        <%
                                        
                                        rsBigClass1.movenext
        loop
        rsbigclass1.close
        set rsbigclass1=nothing%>
        
        </TBODY></TABLE></td>
              </tr>
                
                   <Tr><Td height="25"></Td></Tr>
                
                                                </table>

http://www.corange.cn/archives/2008/04/914.html