Validating security of form submission data

[aewarnick]

On my site I enable users to fill in email and web adresses that will be clickable in their profile. Does anyone know of good validation code that will test to make sure the email and web address they submit are safe for my site?

[matto]

I have a function for e-mail validation:

function checkemail($email)
{
        $email = trim(strtolower($email));
        $regexpattern = '^[\w-\.]{1,}\@([\da-zA-Z-]{1,}\.){1,}[\da-zA-Z-]{2,3}$^';

    return preg_match($regexpattern, $email);
}

when validating form input, just do:

if(!checkemail($_POST['email']))
    // error ...

you can use the body of that function for URLs as well, just google an URL validating regular expression and replace my $regexpattern.