Question

Possible Duplicate:
PHP get index of last inserted item in array

My array is generated the following way:

$_SESSION['add_fail_urls'][] = $_REQUEST['url'];

How do I get a number value of the automatically assigned key []?

Answer 1

<?php $numberOfFailedUrls = count($_SESSION['add_fail_urls']); ?>

Should do the trick. If you want to ensure that you don’t get any notices about the add_fail_urls not existing, then use the following instead:

<?php 
    $numberOfFailedUrls = isset($_SESSION['add_fail_urls']) ? 
        count($_SESSION['add_fail_urls']) : 
        0; 
?>

Edit: I might’ve misinterpreted your post (as of @des comment), as you might want the actual index of the added element instead of the number of elements. If so, here’s a solution brought to you from @romaninsh in the linked question:

<?php 
    end($a);
    $last_id=key($a);
?>