preg_match with complex regular expression

[modune]

Hi dear,
could anyone tell me how I can do a preg_match on an email address with the following pattern found on regexlib(for email validation against rfc2822) :

^{((?>[a-zA-Z\d!#$%&'+-/=?_{|}~]+\x20*|"((?=[\x01-\x7f])[
^"\\]|\\[\x01-\x7f])*"\x20*)*(?<angle><))?((?!\.)(?>\.?[a-zA
-Z\d!#$%&'*+\-/=?^_{|}~]+)+|"((?=[\x01-\x7f])["\]|\[\x01}
-\x7f])")@(((?!-)[a-zA-Z\d-]+(?<!-).)+[a-zA-Z]{2,}|[(((?
(?<![).)(25[0-5]|2[0-4]\d|[01]?\d?\d)){4}|[a-zA-Z\d-]*[a-
zA-Z\d]🙁(?=[\x01-\x7f])[^{\[]]|\[\x01-\x7f])+)])(?(angl}
e)>)$

Problems are the " and the ' and also the ?> in it ...

is there a way to force php to accept the regec without asking questions ...

[zcketcher]

There are an amazing amount of regex examples out there (and I'm going ot offer one more below) but from my research what I have learned is that generally the more complicated the expression the better chance of false positives or the other way around.

What I have found to work best for me is a fairly small expression along with the PHP function: checkdnsrr() which is extreamly usefull in this situation.

function is_valid_email_address($email) {
    if (preg_match("/.+@.+\..+./", $email)) {
        list($username, $domain)=split('@',$email);
        if(!checkdnsrr($domain, 'MX')) {
            return false;
        }
        return true;
    }
    return false;
}

... just another example of email address verification. The nice thing about this is it actually checks if MX records exist for the domain given.