为什么使用枚举时的#define也同样有效？ [英] Why use enum when #define is just as efficient?

问题描述

因此​​，一个枚举是这样的：

So an enum works like this:

enum {
  false,
  true
}

这相当于

int false = 0
int true = 1

我为什么不代替枚举与的#define ？

#define FALSE 0
#define TRUE 1

对我来说，好像他们是可以互换的。我知道，的#define 能够处理参数，因此比枚举完全不同的方式运作。究竟是什么枚举的主要用途时，我们有的#define 的在这种情况下的？

To me, it seems like they are interchangeable. I'm aware that #define is able to handle arguments, hence operates in an entirely different way than enum. What exactly are the main uses of enum when we have #define in this case?

如果我是猜，因为的#define 是preprocessor功能，枚举将有一些运行时的优势。如何遥远的我是谁？

If I were to guess, as the #define is a preprocessor feature, enum would have some runtime advantages. How far off am I?

先谢谢了。

推荐答案

枚举的优势显示出来，当你有你想要映射到数字的东西很长的列表，并且希望能够在中间插入一些那名单。例如，您可以：

the advantages of enum show up when you have a long list of things you want to map into numbers, and you want to be able to insert something in the middle of that list. for example, you have:

pears 0
apples 1
oranges 2
grapes 3
peaches 4
apricots 5

现在你想要把橘子橘子后。与＃定义，你必须重新定义葡萄，桃，杏的数字。用枚举，它会自动发生。是的，这是一个人为的例子，但希望它给你的想法。

now you want to put tangerines after oranges. with #defines, you'd have to redefine the numbers of grapes, peaches, and apricots. using enum, it would happen automatically. yes, this is a contrived example, but hopefully it gives you the idea.

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