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
Here's what I would do (cut some code out for quickness):
HTML (you don't require javascript void code if using jQuery):
<ul id="set-display">
<li><a href="" id="list">Listview</a></li>
<li><a href="" id="grid">Gridview</a></li>
</ul>
jQuery:
$('#set-display a').click(function(e) {
var type = $(this).attr('id');
var view = (type === 'grid') ? 'gridview' : 'listview';
$.post('library/fx.behaviour.php', { display: view });
// you can use the view or type variable to trigger your other code
});
PHP:
session_start(); // if not called already
// if POST display not empty and is expected string then use it, otherwise default to 'listview'
$_SESSION['display'] = ( ! empty($_POST['display']) && in_array($_POST['display'], array('listview', 'gridview'))) ? $_POST['display'] : 'listview';
I used $_POST['display'] rather than setdisplay for naming consistency. It might also be worth checking your jQuery call gets a valid 200 response. In Chrome you can do this by going to the Inspector, selecting the network tab, click the button, and watch for the request.
Specify the data and dataType options:
var jsonstr = JSON.stringify(result);
$.ajax({
type:"POST",
url: "ajax.php",
data:'json=' + jsonstr,
dataType:'json',
success: function(){
alert('Test results submitted!');
}
});
From php, you can get json string using:
$_POST['json'];
My suggestion from your previous question still stands: please compare session ids.
The solution might be as simple as your browser not accepting session cookies.
You retrieve the session id by calling session_id(). Do that right after session_start() it should give you a constant value if the session is the same. Otherwise for every request a new session is instantiated.
Also check C:wamptmp. A gazillion files in this directory might indicate fresh sessions for each request.
EDIT Since we've confirmed new sessions per request, it's time to find out whether session cookies are accepted. Check the settings of your browser and confirm that a cookie for your domain (I guess it's "localhost") with the name PHPSESSID can be found.
Simply put: You can't, directly.
PHP is a server-side language while javascript is a client-side one, which means that there's no other connection between them other than the document you receive and interacts with you. The sessions are stored and managed by the server.
You can, however, as War10ck suggests, call to a server-side script that clears the session. Something like this:
PHP:
<?php
/*
* session_start();
* Starting a new session before clearing it
* assures you all $_SESSION vars are cleared
* correctly, but it's not strictly necessary.
*/
session_destroy();
session_unset();
header('Location: continue.php');
/* Or whatever document you want to show afterwards */
?>
HTML/javascript:
<script type="text/javascript">
function logout() {
document.location = 'logout.php';
}
LogoutButton.addEventListener('click', logout, false);
</script>
<button id="LogoutButton">Log out</button>
Or even performing an asynchronous call:
function logout() {
var xhr = new XMLHttpRequest();
xhr.onload = function() {
document.location = 'continue.php';
}
xhr.open('GET', 'logout.php', true);
xhr.send();
}
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:
Javascript:
PHP (backend.php):