- filter_var: documentation ( source)
<?php
$emails = [
"john.doe@example.com",
"john.doe@example.com",
"john.doe@example.com",
"john.doe@example.com",
"john.doe@example.com",
"john.doe@example.com",
];
if (filter_var($email, FILTER_VALIDATE_EMAIL)) {
echo("$email is a valid email address");
} else {
echo("$email is not a valid email address");
}