String validation

[Anon]

I want to be able to validate form input for usernames. Basically eliminate all illegal characters that are not allowed in standard e-mail addresses before the @ sign.

I.e. only A-Z, a-z, 0-9, and - and _.

Thanks for your help 🙂

[tijger]

look at: http://www.php.net/manual/en/function.ereg.php

in the 'User Contributed Notes' there is much to be found on validating emailaddresses.

greetings.

[cordex]

Check out ereg() and eregi() in the manual.

[Anon]

I figured it out -- sorry I posted. Haha.

For all those who are wondering how I did it or were as clueless as I was 15 minutes ago:

I'm basically doing a:

if(preg_match("/[^\w]/", $username))

Thanks to all who responded.