c++ - 位掩码 : Set different states of an object via set method

Question

我有一种 Material ，可以是热的或冷的，白色的或黑色的。状态可以是热和白、热和黑、冷和白、冷和黑。我有以下类(class)

   class myMaterial
    {
    public:
        enum state
        {
            DEFAULT     = 0,
            HOT         = 1 << 0,
            WHITE       = 1 << 1
        };

        void SetState(int);

    private:
        int m_state;
    };


    void myMaterial::SetState(int state)
    {
        m_state = state;
    }

现在在 main() 中，我调用 SetState 方法来设置这些状态

myMaterial material;
material.SetState(myMaterial::HOT);

下面的位运算是否正确，设置所有类型的状态

HOT and WHITE  =>  myMaterial::HOT | myMaterial::WHITE
HOT and BLACK  =>  myMaterial::HOT | ~myMaterial::WHITE
COLD and WHITE =>  ~myMaterial::HOT | myMaterial::WHITE
COLD and BLACK =>  ~myMaterial::HOT | ~myMaterial::WHITE

Answer 1

修改后，问题似乎有点不同，不再需要@adrin 的每个属性 2 位的解决方案。

现在只是:

HOT and WHITE = myMaterial::HOT | myMaterial::WHITE
HOT and BLACK = myMaterial::HOT
COLD and WHITE = myMaterial::WHITE
COLD and BLACK = 0

如果你添加一个额外的位来说明状态是否已知:

UNKNOWN = 0
HOT and WHITE = myMaterial::HOT | myMaterial::WHITE | myMaterial::KNOWN
HOT and BLACK = myMaterial::HOT | myMaterial::KNOWN
COLD and WHITE = myMaterial::WHITE | myMaterial::KNOWN
COLD and BLACK =  myMaterial::KNOWN