Then, they take that amount and they go over and they type that amount into the credit card terminal.
然后他们拿走了那些钱,检查一下,然后把数额输入信用卡终端机。
In a compiled language, you have an intermediate step, in which you take the source code, it runs through what's called a checker or a compiler or both, and it creates what's called object code.
而在编译语言里,你就会经过一个中间的步骤,在这种语言里输入源码后,先经过过滤器,或者编译器检查后,它会创建一个叫做目标代码的东西。
Notice in this program I have not checked whether or not the user actually provided input.
就拿这个程序说事吧,我们根本没有检查,用户到底有没有输入。
It's going to do a lot of type checking for you before it actually passes things back.
它会在将输入值进行计算之前,做很多类型检查。
Oh wait a minute, that's a little different than what we did last time, right?
这同我上次做的有点不同了,是么?,上一次我们检查了输入?
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。
The format is the same. I'm going to ask for some input, and then I am going to use that procedure to check, is this the right type of value. And I'm trying to use that to do the coercion if you like. Same thing if it works, I'm going to skip that, if it not, it's going to throw the exception.
格式是一样的,我需要一些输入,然后我要用一个过程来检查,是否是正确的值,然后你就可以做强制转换了,如果能运行,那是一样的,我打算跳过这段,如果不正确,那就会抛出一个异常。
I probably whip out a do while loop very rarely, but very often when programming games or any program that takes user input and has to check that user input and yell at the user if they're messing with you or aren't providing what's expected.
我可能很少用do,while,循环,但常常是,当编制程序游戏或需要用户输入的程序是,需要检查用户的输入并提醒用户,如果他们干扰了你,或没有提供所期望的输入。
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