[PHP] Spanish NIF validation - https://github.com/mpijierro/identity

validate_nif.php

<?php

function validateNif($nif) {
    $nifRegEx = '/^[0-9]{8}[A-Z]$/i';
    $nieRegEx = '/^[XYZ][0-9]{7}[A-Z]$/i';
    $letras = "TRWAGMYFPDXBNJZSQVHLCKE";
    if (preg_match($nifRegEx, $nif)) {
        return ($letras[(substr($nif, 0, 8) % 23)] == $nif[8]);
    } else {
        if (preg_match($nieRegEx, $nif)) {
            if ($nif[0] == "X") {
                $nif[0] = "0";
            } else {
                if ($nif[0] == "Y") {
                    $nif[0] = "1";
                } else {
                    if ($nif[0] == "Z") {
                        $nif[0] = "2";
                    }
                }
            }
            return ($letras[(substr($nif, 0, 8) % 23)] == $nif[8]);
        }
        return false;
    }
}