Online PHP editor | refs for 7GMlc

<?php function matchIndetifier($str) { if ($str != preg_replace("/[^0-9a-z]/i", "", $str)) { //Invalid contains characters other than a-zA-Z0-9. } if (isnumeric($str)) { //999999 } if ($str != preg_replace("/\d/", "", $str)) { //At this part, it's not numeric, but still has numbers. Invalid. } if (ucfirst($str) == $str) { //Ullllll } if (strtolower($str) == $str) { //llllll } if (strtoupper($str) == $str) { //UUUUUU } }