Setting a PHP $_SESSION['var'] using jQuery

Question

I need to set a PHP $_SESSION variable using the jQuery. IF the user clicks on an image I want to save a piece of information associated with that image as a session variab

Answer 1

A lot of responses on here are addressing the how but not the why. PHP $_SESSION key/value pairs are stored on the server. This differs from a cookie, which is stored on the browser. This is why you are able to access values in a cookie from both PHP and JavaScript. To make matters worse, AJAX requests from the browser do not include any of the cookies you have set for the website. So, you will have to make JavaScript pull the Session ID cookie and include it in every AJAX request for the server to be able to make heads or tails of it. On the bright side, PHP Sessions are designed to fail-over to a HTTP GET or POST variable if cookies are not sent along with the HTTP headers. I would look into some of the principles of RESTful web applications and use of of the design patterns that are common with those kinds of applications instead of trying to mangle with the session handler.