虽然您将直接在Invoice . php上创建它，但是您可以设想数据来自于数据库、web服务或某种网上购物车系统。

PHP, but you can imagine the data coming from a database, web service, or some sort of online shopping cart system.

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本文研究的在线cd销售系统实现了用户端在线浏览CD信息、开通网上购物车、在线提交订单等功能。

This paper studies the online CD sales system by end users browse the CD online information, and launched online shopping cart. Submitting orders online and other functions.

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在本网上购物系统中，顾客能够方便的进行用户注册，查看商品，并可以将满意的商品加入购物车。

This web shopping system is very convenient for customers to register, view all kinds of products and add what they like to shopping cart.

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