Please enter a valid input tray number for the banner page.

请输入有效的分隔页进纸盒编号。

youdao

A new message is created on output, so you can use any valid input message.

新的消息是根据输出创建的，因此您可以使用任何有效的输入消息。

youdao

A positive test is when you put in a valid input and expect some action to be completed in accordance with the specification.

正向测试是指，当你输入一个有效的输入并且期望软件能够完成一些根据说明书规定的行为。

youdao

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。

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