Username Character Limitations.

[ataria]

Hopefully I got the title right..
alright, what I am looking to do..
is to have the username be a-z, A-Z, 0-9 ONLY.


In an if statement please. (if possible).


thanks in advance!

[marcus]

[code]
if (!ereg("~!@#$%^&*()_+=-,./<>?;':"[]\{}|",$username))
    {
      echo "$username is not a valid username";
    }
[/code]

[trq]

I swear this question was asked half hour ago.

[code=php:0]
if ( preg_match('/^[a-zA-Z0-9_]+$/', $user) ) {
  // valid
}
[/code]

[brendandonhue]

[code=php:0]
if(ctype_alnum($username))
{
  //valid
}
[/code]

[ataria]

Awesome.
Thanks guys!

[ataria]

Would it matter if I used all 3?

such as,

if (!ereg("~!@#$%^&*()_+=-,./<>?;':"[]\{}|",$username))
    {
      echo "$username is not a valid username";
    }
elseif ( preg_match('/^[a-zA-Z0-9_]+$/', $user) ) {
  // valid
}
elseif(ctype_alnum($username))
{
  //valid
}


?

[marcus]

I would stick with one of them. Use thorpes.

[ataria]

Alright.
Thanks!

[brendandonhue]

[quote author=mgallforever link=topic=116102.msg472869#msg472869 date=1164331334]Use thorpes.
[/quote]
Out of curiosity, why that one?

[ataria]

Hey.
Would that make spaces not allowed?

[marcus]

It would make it so only a-z, A-Z and 0-9 are allowed.

[ataria]

I take that as a yes. XD

[marcus]

And brendan, I chose his because I wasn't sure on ataria's PHP Experience level and to show that it would only include those.