Contact Form Validating Email & Non-Latin Characters - php

Question

I am having problems making a website with a contact form.
First of all, any email address entered it spews out as invalid.
Also, I have a expectancy for the name, and I'm not sure how to add special characters (Eg. É) and spaces for the last name.
Here is the existing PHP:
$error_message = "";
$email_exp = "/^[A-Za-z0-9._%-]+#[A-Za-z0-9.-]+\.[A-Za-z];{2,4}$/";
if (!preg_match($email_exp, $email)) {
$error_message .= '<b> The Email Address you entered does not appear to be valid. </b> <br/>';
}
$string_exp = "/^[A-Za-z.'-]+$/";
if (!preg_match($string_exp, $name)) {
$error_message .= '<b> The Name you entered does not appear to be valid. </b> <br/>';
}
if(strlen($subject) < 3){
$error_message .= '<b> The Subject you entered does not appear to be valid. </b> <br/>';
}
if(strlen($message) < 2){
$error_message .= '<b> The Message you entered does not appear to be valid. </b> <br/>';
}
Updated PHP for #J. Robertson:
<?php
if (isset($_POST['email'])){
// email info
$email_to ="example#example.com";
$email_subject = $_POST['subject'];
$email_from = $_POST['email'];
//error code
function died($error) {
echo "I am sorry, but there seems to be error(s) found within the form you submitted. <br/>";
echo "The error(s) will appear below: <br/> <br/>";
echo $error. "<br/><br/>";
echo "Please go back and fix these error(s). <br/>";
die();
}
//validation
if(!isset($_POST['name']) ||
!isset($_POST['email']) ||
!isset($_POST['subject']) ||
!isset($_POST['message'])) {
died('I am sorry, but there appears to be a problem with the form you submitted.');
}
$name = $_POST['name'];
$email = $_POST['email'];
$subject = $_POST['subject'];
$message = $_POST['message'];
//expected strings
$error_message = "";
$email_exp = '/[^\s]*#[a-z0-9.-]*/i';
if (!preg_match($email_exp, $email)) {
$error_message .= '<b> The Email Address you entered does not appear to be valid. </b> <br/>';
}
$string_exp = "/^[A-Za-z.'-]+$/";
if (!preg_match($string_exp, $name)) {
$error_message .= '<b> The Name you entered does not appear to be valid. </b> <br/>';
}
if(strlen($subject) < 3){
$error_message .= '<b> The Subject you entered does not appear to be valid. </b> <br/>';
}
if(strlen($message) < 2){
$error_message .= '<b> The Message you entered does not appear to be valid. </b> <br/>';
}
if(strlen($error_message) > 0 ){
died($error_message);
}
$email_message = "Form Details below.\n\n";
//sanitization
function clean_string($string){
$bad = array("content-type", "bcc:", "to:", "cc:", "href");
return str_replace($bad, "", $string);
}
$email_message .= "Name:" . clean_string($name) . "\n";
$email_message .= "E-Mail:" . clean_string($email) . "\n";
$email_message .= "Subject:" . clean_string($subject) . "\n";
$email_message .= "Message:" . clean_string($message) . "\n";
//email headers
$headers = 'From: ' .$email_From . '\r\n'. 'Reply-To' .
$email. "\r\n" .
'X-Mailer: PHP/' . phpversion();
#mail($email_to, $email_subject, $email_message, $headers);
}
?>

Answer 1

I suspect the problem lies with your reg ex. Using http://gskinner.com/RegExr/ to test it against test#test.com, your reg ex does not pick up even that basic email address.
It's highly unlikely you'll come up with a regex that covers all email possibilities- it may be more worthwhile to simply check for an '#' sign, and then send a test email to the server to see if it's valid.
Otherwise, if you'd like a valid regex to test against, try
/[^\s]*#[a-z0-9.-]*/i