Mysql and onbeforeunload

Question

Hi I'm trying to delete a row in a mysql database when the user leaves a page on my website but it's not working for some reason. I know the onbeforeunload works because if i delete everything in there and just put alert("test"); the alert shows. Can this not be done? My code is below thank you for any help

Javascript

<script type="text/javascript">
window.onbeforeunload = function(){ 
    var id = document.reset.id.value;
    $.ajax({
        url: "Resetter.php",
        type: "GET",
        data: {'id':id},
        success: function (response) {
            alert(response);
        }
    });
}
</script>

PHP

<?PHP
    $id = $_GET['id'];
    $link = mysql_connect('localhost', 'root', 'root');
    mysql_select_db("Colleges");
    $delete = mysql_query("DELETE FROM `Table` WHERE `ID`='" . $id . "'");
    mysql_close();
    die();
?>

Answer 1

Since you're closing the page you're closing the connection to the server and therefore it won't wait for you Ajax call to finish. This isn't how onbeforeunload works. It's client-side only. Also note, that onbeforeunload can be a little finicky in my experience and doesn't account for every way a user can move away from your page.

To accomplish what you want, you'd have to set up some sort of long polling. Here's an example using PHP on the server-side: http://blog.perplexedlabs.com/2009/05/04/php-jquery-ajax-javascript-long-polling/

You could also use something like Node.js to listen for connections and disconnections from the page.