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 variable in php.

I think I can do this by calling a php page or function and appending that piece of info to the query string.

Any ideas. I have found little help through google.

thanks mike

Answer 1

Might want to try putting the PHP function on another PHP page, and use an AJAX call to set the variable.

Answer 2

Whats you are looking for is jQuery Ajax. And then just setup a php page to process the request.

Answer 3

You can't do it through jQuery alone; you'll need a combination of Ajax (which you can do with jQuery) and a PHP back-end. A very simple version might look like this:

HTML:

<img class="foo" src="img.jpg" />
<img class="foo" src="img2.jpg" />
<img class="foo" src="img3.jpg" />

Javascript:

$("img.foo").onclick(function()
{
    // Get the src of the image
    var src = $(this).attr("src");

    // Send Ajax request to backend.php, with src set as "img" in the POST data
    $.post("/backend.php", {"img": src});
});

PHP (backend.php):

<?php
    // do any authentication first, then add POST variable to session
    $_SESSION['imgsrc'] = $_POST['img'];
?>

Answer 4

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.

Answer 5

in (backend.php) be sure to include include

session_start();

-Taylor http://www.hawkessolutions.com