Cpp

重载的运算符是成员函数时

scorlw 发布于

重载的运算符是成员函数时

c++

当重载的运算符是成员函数时，this绑定到左侧运算符对象（例如重载+运算符，则默认+左侧的参数为this（或者this的成员））。成员运算符函数的参数数量比运算符对象的数量少一个；至少含有一个类类型的参数；

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class CWeight
{
public:
	CWeight(int iIn){m_iWeight = iIn;};
	CWeight operator+(const CWeight& other);
	CWeight& operator=(const CWeight& other);
public:
	int m_iWeight;
};
CWeight CWeight::operator+(const CWeight& other)
{
	return CWeight(this->m_iWeight + other.m_iWeight);  // 注意这里, 调用了实际的加法,但是本实例的数据作为了左操作数, 我特意加了this->,其实是可以省略的.
}
CWeight& CWeight::operator=(const CWeight& other)
{
   m_iWeight = other.m_iWeight;
   return *this;
}

int main()
{
	CWeight w1(10);
	CWeight w2(20);
	CWeight w3 = w1 + w2;
	printf("w1 = %d, w2 = %d, w3 = %d\n", w1.m_iWeight, w2.m_iWeight, w3.m_iWeight);
    system("pause");
    return 0;
}

输出：

1
w1 = 10, w2 = 20, w3 = 30