C++为一个基类编写拷贝赋值运算符出现"!="无法与操作数匹配的问题

Question

Quote& operator =(const Quote& rhs)
    {
        if (*this != rhs)
        {
            bookNo = rhs.bookNo;
            price = rhs.price;
        }
        std::cout << "Quote:copy =()" << endl;

        return *this;
    }

啥情况
请求各位帮忙！

Answer 1

if(this!=&rhs)