枚举范围可能吗？ [英] are ranges possible with enums?

问题描述

在C＃中，您可以在枚举类型中使用数字范围吗？

In C#, can you use number ranges in enum types, for example

public enum BookType
{
    Novel = 1,
    Journal = 2,
    Reference = 3,
    TextBook = 4 .. 10
}

编辑：之所以需要这样做，是因为将数字转换为枚举类型，例如：

The reason this is needed is to cast from a number to the enum type, eg:

int iBook = 5
BookType btBook = (BookType)ibook
Debug.Print "Book " + ibook + " is a " btBook

，预期输出为：书5是教科书

and the expected output is: Book 5 is a TextBook

推荐答案

根据C＃标准（p612，C＃编程语言），赋予枚举的值必须为常量整数（或任何类似的类型-long，byte，sbyte，short等），因此值的范围无效。

According to the C# standard (p612, The C# Programming Language) the value given to an enumeration must be a constant integer (or any similar type - long, byte, sbyte, short, etc), so a range of values isn't valid.

我的编译器（VS2008）符合规范。

My compiler (VS2008) agrees with the spec.

由于您无法在枚举中重复名称，因此获得的最接近的内容是这样的：

Since you can't repeat names within an enumeration, the closest you'll get is something like this:

public enum BookType
{
    Novel = 1,
    Journal = 2,
    Reference = 3,
    TextBook4 = 4,
    TextBook5 = 5, ...
    TextBook10 = 10
}

这实际上很丑。也许枚举不是解决您特定问题的方法...

Which is actually pretty ugly. Perhaps an enum is not the solution to your particular problem ...

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