树形菜单问题

不用帧结构，进入不同页面时会刷新页面，怎么保留树形菜单的展开状态，就是要知道自己所在页面是那部分。代码如下
surfmap.js
//

-----------------------------------------------------------------------

-----
// Private section.
//
// The variables and functions in this section are used internally by

the script
// and shouldn't be accessed directly from outside.
//

-----------------------------------------------------------------------

-----

// Global variables
var items = new Array(); // array of all items in

the sitemap
var topItems = new Array(); // top level items only
var browser = "OTHER"; // browser version (IE,

NS or OTHER)
var selectedItem = null; // current selected item
var style = null; // site map style
var scriptURL = null; // URL to the script

folder
var expandTopItems = null; // true to expand top

level items
var mouseOverColor = "#FFFFFF"; // mouse over color
var selectedColor = "#FFFFFF"; // selected color
var selectedBackground = null; // selected background

color

-----------------------------------------------------------------------

-----
// Calculates the Y coordinates of all visible sitemap items.
//

-----------------------------------------------------------------------

-----
function adjustY()
{
if ( browser != "NS" )
return;

var y = 0;
var minWidth = 0;
var minHeight = 0;
for ( var i=0; i

 1<items.length; (="" )="" +="items[i].obj.clip.height;" i++="" if="" items[i].obj.clip.width="" items[i].obj.left="0;" items[i].obj.top="y;" items[i].obj.visibility="show" y="" {=""> minWidth )   
 2minWidth = items[i].obj.clip.width;   
 3minHeight += items[i].obj.clip.height;   
 4}   
 5}   
 6document.sitemap.clip.right = minWidth;   
 7document.sitemap.clip.bottom = minHeight;   
 8}   
 9  
10  
11  
12//   
13  
14\-----------------------------------------------------------------------   
15  
16\-----   
17// Colapses a given item, hiding its entire subtree.   
18//   
19  
20\-----------------------------------------------------------------------   
21  
22\-----   
23function colapse( siteItem )   
24{   
25if ( selectedItem == siteItem )   
26selectItem( null );   
27for ( var i=0; i<siteitem.children.length; "<table="" (="" )="" );="" ;="" \-----="" \-----------------------------------------------------------------------="" _writeln(="" border="0" browser="IE" cellpadding="0" cellspacing="0" colapse(="" display()="" displays="" else="" function="" i++="" if="" siteitem.children[i]="" siteitem.children[i].obj.style.display="none" siteitem.children[i].obj.visibility="hide" sitemap="" style="position:relative; font-size: 9pt; font-family: 宋体; " the="" {="" }=""><tr><td align="left" valign="top">" );   
28  
29for ( var i=0; i<topitems.length; ""="" "<="" (="" )="" );="" _writeln(="" browser="IE" i++="" if="" renderitem(="" td="" topitems[i],=""></topitems.length;></td></tr>" );   
30else if ( browser == "NS" )   
31window.onResize = restoreIcons;   
32else   
33return;   
34  
35for ( var i=0; i&lt;topItems.length; i++ )   
36{   
37var siteItem = topItems[i];   
38if ( browser == "IE" )   
39siteItem.obj.style.display = "block";   
40else if ( browser == "NS" )   
41siteItem.obj.visibility = "show";   
42if ( (expandTopItems) &amp;&amp; (siteItem.children.length != 0) )   
43{   
44expand( siteItem );   
45siteItem.opened = true;   
46updateIcons( siteItem );   
47}   
48}   
49adjustY();   
50}   
51  
52  
53  
54//   
55  
56\-----------------------------------------------------------------------   
57  
58\-----   
59// Expands a given item, re   
60\---------------------------------------------------------------   
61  
62  
63var oRange=document.body.createTextRange();   
64if (oRange.findText('这里是你的节点名称'))   
65{oRange.select();}</siteitem.children.length;></items.length;>