A simple regular expression (regex) for validating email address using PHP which I used mostly on my web apps.
I love being a Web developer and it’s been a lot of fun — this is one of them

[php]<?php
function validateEmail($email) {
if (ereg("^[_a-zA-Z0-9-]+(\.[_a-zA-Z0-9-]+)*@+([_a-zA-Z0-9-]+\.)*[a-zA-Z0-9-]{2,200}\.[a-zA-Z]{2,6}$", $email)) {
return true;
} else {
return false;
}
}
?>[/php]

Usage:
[php]<?php
if (validateEmail($email)) {
// Email address is valid, do your process here…
} else {
// Email address is not valid, do your process here…
}
?>[/php]