给胖子演示一下c++类成员函数中能访问同类对象的私有数据成员。

access_private_data.cpp

#include <iostream>
using namespace std;

class Car {
  public:
  Car(int num, const string& engineer) : m_nWheel(num), m_strEngineer(engineer) {}
  void display(Car& car);
  
  private:
  void joke(){}
  
  private:
  int m_nWheel;
  string m_strEngineer;
};

void Car::display(Car& car) {
  car.joke();
  cout << "Car's made up:\n";
  cout << "Wheel number: " << car.m_nWheel << endl;
  cout << "Engineer name: " << car.m_strEngineer << endl;
}

int main(int argc, char** argv) {
  Car A(4, "V12"),B(6, "BMW");
  A.display(B);
  return 0;
}