- var_dump: documentation ( source)
- filter_var: documentation ( source)
<?php
$email = '"this is a valid address"@example.com';
$checked = filter_var($email, FILTER_VALIDATE_EMAIL);
var_dump($email, $checked);
$email = '123@example.com';
$checked = filter_var($email, FILTER_VALIDATE_EMAIL);
var_dump($email, $checked);