Question

I need a regex that allow user to insert a password in a field.
But the only allowed regex are [A-Za-z0-9] ok, but also “space”, “.”, “_”, “-“.
How can is possible allow the special chars I listed, but NOT TO FORCE user to use that?
On the other hand, disallow all the other special chars.

Is it possible?

With this code I check the quality of the password, but not sufficient for my goal cause I cannot manage the special chars:

            else if ($check_strength && (!preg_match("/[0-9]/", $newpwd) || !preg_match("/[^A-Za-z0-9]/", $newpwd))) {
            $rcmail->output->command('display_message', $this->gettext('passwordweak'), 'error');
        }

I’ve solved my problem with this one:

"/^[A-Za-z0-9\.\-\_]+$/"

Answer 1

echo preg_match("/^[A-Za-z0-9 ._-]+$/", '-a. s_d'); // 1

or more abbreviated:

echo preg_match("/^[\w .-]+$/", '-a. s_d'); // 1