可以放多条留言栏的代码，在软件中可以是作为备忘，或作为问答题，或作为登陆等。该留言还可以多次重复修改，使用方便。-Can take a number of bar code message, the software can be as a reminder, or as questions, or as a landing. The guestbook can be repeatedly modified and easy to use.