this指针的作用是什么啊?在哪些情况下可以用?可以举个例子吗?谢谢!
例子:+ 法重载[CODE]class complex {private: double real,imag;public: complex(double r=0.0,double i=0.0){real=r;imag=i;} complex operator +(complex c2); double outputreal(){return real;} double outputimag(){return imag;}};complex complex::operator +(complex c2){ return complex(this->real+c2.real,this->imag+c2.imag); //注意这里的this的使用}void main(){ complex a(3.2,4),b(2.3,5); complex c=a+b; cout<<"a:"<<a.outputreal()<<"+"<<a.outputimag()<<"i"<<endl; cout<<"b:"<<b.outputreal()<<"+"<<b.outputimag()<<"i"<<endl; cout<<"a+b="<<c.outputreal()<<"+"<<c.outputimag()<<"i"<<endl;}[/CODE]