validate username with ereg

[parka]

This was an example from a book and it didn't work.

Is there something wrong with the code or is it a php.ini thing?

 

$username = 'parka';
$valid = ereg($username, '[[:alnum:] _-]{5,10}');
if (!$valid){
    print "username is invalid";
}

 

[Orio]

I'd rather use:

 

$valid = eregi($username, '[a-z0-9_\-]{5,10}');

 

Orio.