- substr: documentation ( source)
- time: documentation ( source)
- mt_rand: documentation ( source)
- hash: documentation ( source)
- strtoupper: documentation ( source)
<?php
$generated_id = substr('abcdefghijklmnopqrstuvwxyz', mt_rand(0,25), 1) . mt_rand(0,9) . substr(hash("sha256", time() . mt_rand(100000,999999)),0,6);
strtoupper($generated_id);
echo $generated_id;