if (empty($_SERVER['HTTP_X_REQUESTED_WITH']) || $_SERVER['HTTP_X_REQUESTED_WITH'] != 'XMLHttpRequest') {return;}
if (empty($_POST['action'])) {return;}
$result = '';
switch ($_POST['action']) {
    case 'read':
    $sql = 'SELECT * FROM `items` WHERE status=1 LIMIT 100';
        $query = $modx->query($sql);
        if ($query) {
            while ($i= $query->fetch(PDO::FETCH_ASSOC)) {
                $result .= $i['id'];
            }
        }
    break;
    case 'insert':
        $item_name = (int)$_POST['item_name'];
        $item_text=mysql_real_escape_string($_POST['item_text']);
        $status = 1;
        $sql ="insert into `items` (item_name,item_text,status) values ('".$item_name."','".$item_text."','".$status."')";
        $stmt = $modx->prepare($sql);
        $stmt->execute();
        $res = 'ok';
        break;
}
if (!empty($res)) {
    die($res);
}