Email addresses are used for everything. Registrations, usernames, lead generation… Everything. They are as unique as a telephone number or physical address and require validation just like any other piece of data.

I’ve come across a lot of poorly written email validation scripts, but this one has risen from the ashes in a blazing glory every single time. And what’s more is you can convert it to a JavaScript validation function too! ^_^

<?php

/* validate an email address. */
function jValidateEmailAddress($sInput) {
	return eregi("^[_A-Za-z0-9-]+(\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\.[A-Za-z0-9-]+)*(\.[A-Za-z]{2,3})$", $sInput);
}

?>

Extra credit bonus stage! I converted this function to JavaScript for you.

<script type="text/javascript">

/* validate an email address. */
function jValidateEmailAddress($sValue) {
	var $oRegExp = /^[_A-Za-z0-9-]+(\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\.[A-Za-z0-9-]+)*(\.[A-Za-z]{2,3})$/;
	return $oRegExp.test($sValue);
}

</script>

Tags: PHP, Regex, Validate