Trying to do simple regex, but not getting it.

[nakins]

I have a html form that will transfer inputs into a pdf. This is an application for a school related program. So, it is just asking for things like names, address, grades, etc. The fields are simple single item inputs, like first name, mid, last name. I'm trying to limit input to just what you would expect. For example, "Bill" in the first name field, should just be a-zA-Z.  But, if I enter bill&, it gives it a pass. Maybe my logic is wrong or just my idea of this all is wrong. The code is as follows.  What I think I'm saying here is if the string matches any numbers or the special characters in the list, then it should fail and die.

 

$pat='^[0-9./\|#$%^&*()!~-={}<>?:]$';
            if(empty($_POST['first']) || ereg($pat,$_POST['first'])){
                die('Invalid input for first name field.');
            }else{
                $data['first']=$_POST['first'];
            }

 

Could someone give me a little direction here?

 

[nrg_alpha]

I would start off by using preg instead of ereg, as ereg will not be included in the core of PHP 6 (it will only be available as an extension).

If you want $_POST['first'] to only have letters of the alphabet (a-zA-Z), you can simply pass $_POST['first'] through ctype_alpha as well as empty()...

 

$_POST['first'] = array('billy', 'BILLY', 'BilLy', '_billy', 'bill101', 'billy!', NULL, '0', FALSE, '', ' ');
foreach($_POST['first'] as $val){
   echo $val,(ctype_alpha($val) && !empty($val))? ' = Valid!<br />' : ' = Invalid!<br />';
}

 

Output:

billy = Valid!
BILLY = Valid!
BilLy = Valid!
_billy = Invalid!
bill101 = Invalid!
billy! = Invalid!
= Invalid!
0 = Invalid!
= Invalid!
= Invalid!
= Invalid!

[nakins]

Thanks, I'll look to see if ctype thing will work. I don't know if it will work for eveything, however. Like email. Thanks for the heads up on ereg.

[nrg_alpha]

Thanks, I'll look to see if ctype thing will work. I don't know if it will work for eveything, however. Like email.

 

No, it won't work for email, as emails need more than simply [a-zA-Z]

But for the firstname post, ctype_alpha() and !empty should work just fine.