function genCode($length = 10) {

    $characters = abcdefghijkmnpqrstuvwxyzABCDEFGHJKLMNPRSTUVWXYZ;

    $charactersLength = strlen($characters);

    $randomString = ;

    for ($i = 0; $i < $length; $i++) {

        $randomString .= $characters[rand(0, $charactersLength - 1)];

    }

    return $randomString;

}