<SELECT onchange="window.location.href=this.options

<SELECT onchange="window.location.href=this.options
    [this.selectedIndex].value">
<OPTION VALUE="0">categories</OPTION>
<OPTION VALUE="cat1">1</OPTION>
<OPTION VALUE="cat2">2</OPTION>
<OPTION VALUE="cat3">3</OPTION>
</SELECT>

Code (markup):

instead of a standard menu i want a drop down menu.
how can i change it so if i go to 'cat2' the selections stays on 'cat2'?
(also on the category it has pages)

 

When should it stay on 'cat2'? When you go to the next page? When you com back to this page?

 

the options are from index.php,so when they select one it stays on that option in the menu.