Why can I access a private method from outside in C ++?

Question

Possible duplicate:
Why is it allowed to call a private virtual method of a derived class using a base class pointer?

I recently met a strange question, plz refers to the following code:

#include <iostream> using namespace std; class A { public: virtual void disp() { cout<<"A disp"<<endl; } }; class B : public A { private: void disp() { cout<<"B disp"<<endl; } }; int main() { A a; a.disp(); A *b = new B(); b->disp(); } 

and output:

 A disp B disp 

I am wondering why the b pointer can access disp ()? This is personal! Is not it?

Answer 1

disp () is publicly available since you call it via A * and disp () is declared as public in A. Since it is virtual, the B version of disp is called, but this does not affect the publication or private.

Answer 2

This is for language design. However, it is bad practice to strengthen the level of protection of methods when receiving