Question

让我们假设我想创建一个带有二进制标志的BitField类和一个构造函数，用于定义其中有多少个标志：BitField bitField(500)。创建这样一个课程的最佳方法是什么？如果我能读取并在偏移处设置标志并在位域getState(int index) const;上执行按位操作，那将会很酷。谢谢！

Answer 1

如果您要求bitset，可以参考STL的实施。

Answer 2

以下是我的建议（不包括实施本身）：

#include <limits.h>

template<unsigned int SIZE>
class BitField
{
public: //Constructors + Destructor
    BitField();
    virtual ~BitField();
    //-----------------------------------------------------------------------------
public: //Assignment Operators
    virtual const BitField& operator=(const BitField& bitField);
    virtual const BitField& operator|=(const BitField& bitField);
    virtual const BitField& operator&=(const BitField& bitField);
    virtual const BitField& operator^=(const BitField& bitField);
    virtual const BitField& operator<<=(unsigned int shift);
    virtual const BitField& operator>>=(unsigned int shift);
    //-----------------------------------------------------------------------------
public: //Unary Operators
    virtual BitField operator~() const;
    //-----------------------------------------------------------------------------
public: //Binary Operators
    friend BitField operator|(const BitField& bitField1,const BitField& bitField2);
    friend BitField operator&(const BitField& bitField1,const BitField& bitField2);
    friend BitField operator^(const BitField& bitField1,const BitField& bitField2);
    virtual BitField operator<<(unsigned int shift) const;
    virtual BitField operator>>(unsigned int shift) const;
    //-----------------------------------------------------------------------------
public: //Binary Comperators
    friend bool operator==(const BitField& bitField1,const BitField& bitField2);
    //-----------------------------------------------------------------------------
protected:
    unsigned char m_flags[(SIZE-1)/CHAR_BIT+1];
};

注意：使用BitField<500> bitField而不是BitField bitField(500)实例化对象。

具有标志数量的BitField作为参数

2 个答案: