<?php require 'ajax.class.php'; $ajax = new ajax($_POST['dataType']); $ajax->set_data('script_name', $_SERVER['PHP_SELF']); // set any data you want in ajax output if (!filter_var($_POST['email'], FILTER_VALIDATE_EMAIL)) { $ajax->send(0, 'the email looks invalid !'); } // $ajax->send method will exit script $ajax->send(1, 'email looks valid');