C ++枚举类整数不适用于数组下标 [英] c++ enum class integer not working for array subscript

问题描述

我有以下枚举类:

enum class EnumClass : int
{
    A = 0, B
};

现在我想用该枚举类型下标到数组:

Now I want to subscript with that enum type to an array:

MyObject arr[2];
.
.
.
MyObject a = arr[EnumClass::A]
MyObject b = arr[EnumClass::B]

不幸的是，我收到以下错误消息:

Unfortunately I get the following error message:

array subscript is not an integer

由于枚举类是强类型的，所以我希望它能起作用.

As enum classes are strongly typed I would expect this to work.

推荐答案

由于枚举类是强类型的，所以我希望它能起作用

As enum classes are strongly typed I would expect this to work

恰恰相反，这就是为什么它不起作用的原因.作用域枚举不会隐式转换为基础类型.改用 static_cast .

On the contrary, that's exactly why it won't work. Scoped enumerations will not implicitly convert to the underlying type. Use static_cast instead.

MyObject a = arr[static_cast<int>(EnumClass::A)];

这篇关于C ++枚举类整数不适用于数组下标的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！