PHP <a href =点击cookie的值

For a site I use one big PHP file wich generate all the pages, I use url transfer for the menu choice and that's what I want to change.

<li><a href="Index.php?s=I">Home<br></a></li>
<li><a href="Index.php?s=Z">About<br></a></li>

I want to loose the ?s=Z from the URL and pass the value 'Z' to a cookie when clicked and then reload the PHP file, read the cookie, and generate the page "About".

I was thinking and playing with "onclick", but this didn't work.

Regards,

Marco

With the help on another question I solved also this problem, it's a work around, but it does the trick.

Basicly the solution was to look if there was a VAR at the end of the URL.

If so, put the VAR in a cookie and reload the page without the URL VAR. After reload, read the cookie and execute the menu option.