But when you start writing programs, especially when we get to web-based stuff where you want -- to check the user's input -- is it valid, is it an email address, -- and all these different scenarios -- it's actually often useful to be able to just enumerate them or rattle them off using this switching construct instead.

但是当你看是写程序时，特别是当我们,使用基于网络的东西，你想要,检查用户的输入-,它是合法的吗？它是不是一个电子邮箱地址？,所有的这些场景-,实际上它常常是有用的，当你用枚举结构列举它们,或者用它来快速地来说出它们。

哈佛公开课 - 计算机科学课程节选

Odds are statistically most of you will tackle something web based although you'll be able to tackle something android based, iPhone based, C based, PHP, really the choice will ultimately be yours, but to think about exactly how to design good software is something you, is certainly a lesson that we want to promote.

你们中很多人,会使用基于网络的方案,虽然你有能力使用基于android，iPhone，C，PHP的方案，的确，最终是你们自己的选择，但是确切地想一想,怎样设计一个好的软件，是我们提倡的经验。

哈佛公开课 - 计算机科学课程节选