PHP how to maintain/update querystring across all links in page
<p>I have a custom e-shop script written in PHP/MySQL. 
On the product pages there is a form using GET with a series of form elements (drop downs, check boxes, sliders etc) who's values are used to construct the final MySQL query for pulling the right products based on the users selections. To construct my query, I go through the $_GET array and construct it accordingly. But on the pages I also have pagination &amp; sorting href links, a "Cancel this filter" href link under each option in the form to reset each form value etc. </p>

<p>My question is, how do I maintain the add the querystring to all links throughout the page so that the variables are maintained in any action (links, form submission, browser back-forth)?</p>
