Changing a variable on href click

[Anon]

This is probably very simple, but it\'s friday afternoon/evening and my brain is slowly siezing up for the weekend..

I have a php file that links to itself:

<a href=\"<?echo \"$PHP_SELF?dirl=$dirl\"?>sort order</a>

I want to change $dirl to either \'ASC\' or \'DESC\', only when that link is clicked.. any ideas from anyone?

[amcgrath]

put this before the link:
$dir1 = ($dir1 == "ASC" ? "DESC" : "ASC");