eregi replaced with preg_match brings error back - php

Question

I am quite new to php so excuse my poor knowledge but I am using an email form for users to register on my web page but I am getting errors running it.
the full script is as follow:
<?php
if(isset($_POST['email'])) {
// EDIT THE 2 LINES BELOW AS REQUIRED
$email_to = "contact#slapmybeat.com";
$email_subject = "New e-mail subscriber";
function died($error) {
// your error code can go here
echo "We are very sorry, but there were error(s) found with the form your submitted. ";
echo "These errors appear below.<br /><br />";
echo $error."<br /><br />";
echo "Please go back and fix these errors.<br /><br />";
die();
}
// validation expected data exists
if
(!isset($_POST['email'])) {
died('We are sorry, but there appears to be a problem with the email your submitted.');
}
$email_from = $_POST['email']; // required
$error_message = "";
$email_exp = "/^[A-Z0-9._%-]+#[A-Z0-9.-]+\.[A-Z]{2,4}$/";
if(!preg_match($email_exp,$email_from)) {
$error_message .= 'The Email Address you entered does not appear to be valid.<br />';
}
if(strlen($error_message) > 0) {
died($error_message);
}
$email_message = "Form details below.\n\n";
function clean_string($string) {
$bad = array("content-type","bcc:","to:","cc:","href");
return str_replace($bad,"",$string);
}
$email_message .= "Email: ".clean_string($email_from)."\n";
// create email headers
$headers = 'From: '.$email_from."\r\n".
'Reply-To: '.$email_from."\r\n" .
'X-Mailer: PHP/' . phpversion();
#mail($email_to, $email_subject, $email_message, $headers);
?>
<!-- include your own success html here -->
Thank you for contacting us. We will be in touch with you very soon.
<?
}
?>
First I had a "eregi depreciated" error because of the initial script which was as follow:
$error_message = "";
$email_exp = "^[A-Z0-9._%-]+#[A-Z0-9.-]+\.[A-Z]{2,4}$";
if(!eregi($email_exp,$email_from)) {
$error_message .= 'The Email Address you entered does not appear to be valid.<br />';
}
After googling it I replaced it with:
$error_message = "";
$email_exp = "/^[A-Z0-9._%-]+#[A-Z0-9.-]+\.[A-Z]{2,4}$/";
if(!preg_match($email_exp,$email_from)) {
$error_message .= 'The Email Address you entered does not appear to be valid.<br />';
}
but now it is giving me the following, although the email adress is correct:
We are very sorry, but there were error(s) found with the form your
submitted. These errors appear below.
The Email Address you entered does not appear to be valid.
Please go back and fix these errors.
any help will be much apreciated

Answer 1

eregi is case-insensitive, preg_match is not.
You have to add i to the end of the pattern (/..../i).

Answer 2

Not a direct answer, but if you want to check for a valid e-mail address, it is a lot easier to use php's built-in filters:
$email = filter_var($email_from, FILTER_VALIDATE_EMAIL);
Now $email will contain the filtered e-mail address or false if the filter failed (not a valid address in this case).

Answer 3

You should escape the "." inside the [] because it will match every character if you don't do it, you'll have:
"/^[A-Z0-9\._%-]+#[A-Z0-9\.-]+\.[A-Z]{2,4}$/i"