Validate Username ??

Anon

Hi all,

Could anybody write a simple (but complicated for me because I am bit lasy 😉) a peice of reguler expression ..

Like I want to validate the the $username should follow the following parameters....

1) it should be in alphanumeric format mean both 0-9 and a-z's combination will be accepted .. it can't be only NUMERIC ..

2) no other charecters(like:,-,+,$,%,^ etc) will be allowed but underscore("_") only.

3) it should not contain any "white-spaces"

Thanx in anticipation

Tabish

van__

Man, I probably shouldn't cause you specifically said you're being lazy and coming here to have us do your work for you...

But I'm a sucker for regexs.
...though this one is a bit too easy.

if (!preg_match('/^{[a-z0-9_]$/i',$username))} {
//deny
}

van__

you may want to force x amount of charcters in a name, this one requires a minimum of six and no more than 20.

<?
if (!preg_match('/^{[a-z0-9_]{6,20}$/i',$username))} {
//deny;
}
?>

Anon

Aaah, but surely a username of 12345678 would validate through that regex? The problem specificed that all-numeric usernames are invalid ;-)

van__

Oh well boo hoo hoo.
I shouldn't have even given him anything,
But since I went ahead and got bitched at because he had some not ALL NUMERIC crap, which I was too tired to even notice...

but if he wants that, he can add another regex after the first one to check for being alphanumeric and then he might even check to make sure it has uppercase and lowecase letters...

preg_match('/[A-Z]{1,}[a-z]{1,}/',$userName)

Anon

Van,

Thanx for giving me the code, but unfortunatly you have said so much about my lazyness. I am a member of PHPbuilder since one year and whatever I have learned, learned from here.

You seems new to me because I am seeing your name from past few weeks. And you are trying to help of every thread, that's really good. And as far as my lazyness is concerned that is just because the EXTRA burdon on me, and hey.. I am not using you people to work for me, because no one is forcing you to give the answer, that's simply your choice...

Anyway thanx for your help..

Regrads
Tabish