Generate random password in php

passwd.php

<?php
function generate_pass($length) {

  $chars = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPRQSTUVWXYZ_-";
    $code = "";
    while (strlen($code) < $length) {
            $code .= $chars[mt_rand(0,strlen($chars))];
        }
    
    return $code;

}
?>