类的命名空间中的C++公共枚举

#include <iostream>

class MyClass {
public:
    enum class Color { RED, GREEN, BLUE };

    void printColor(Color c) {
        switch (c) {
            case Color::RED:
                std::cout << "Color is RED" << std::endl;
                break;
            case Color::GREEN:
                std::cout << "Color is GREEN" << std::endl;
                break;
            case Color::BLUE:
                std::cout << "Color is BLUE" << std::endl;
                break;
        }
    }
};

int main() {
    MyClass obj;
    obj.printColor(MyClass::Color::RED);
    obj.printColor(MyClass::Color::GREEN);
    obj.printColor(MyClass::Color::BLUE);
    return 0;
}