$body = "Пользователь заказал: <br>";
$mail_subject = "Заказ";
$to = "почта";
$mail_headers="content-type:text/html; charset=UTF-8";
foreach($_POST as $key => $array){
$body .= "{$key}: {$array}<br />";
}
mail($to, $mail_subject, $body, $mail_headers);
$arr = $_POST;
$stroka = implode(",", $arr);