C++ 成员函数做友元函数

  1 #include <iostream> // 标准的输入输出
  2 using namespace std;
  3 
  4 class Building;
  5 class goodFriend {
  6 public:
  7     goodFriend();
  8     void visit();
  9     void visit2();
 10     Building* b;
 11 };
 12 class Building {
 13     friend void goodFriend::visit();
 14 
 15 public:
 16     Building(); // 类内申明，类外实现
 17 public:
 18     string m_sittingrookm;
 19 
 20 private:
 21     string m_bedroom;
 22 };
 23 
 24 // 类外实现
 25 Building::Building()
 26 {
 27     this->m_sittingrookm = "卧室";
 28     this->m_bedroom = "客厅";
 29 }
 30 
 31 // 类外实现
 32 goodFriend::goodFriend()
 33 {   
 34     b = new Building;
 35 }
 36 
 37 void goodFriend::visit()
 38 {
 39     cout << "好基友正在参观" << this->b->m_sittingrookm << endl;
 40     cout << "好基友正在参观" << this->b->m_bedroom << endl; // 将goodFriend申明为Building的友元类;
 41 }
 42 
 43 void goodFriend::visit2()
 44 {
 45     cout << "好基友正在参观" << this->b->m_sittingrookm << endl;
 46     //    cout << "好基友正在参观" << this->b->m_bedroom << endl; // 将goodFriend申明为Building的友元类;
 47 }
 48 void test01()
 49 {
 50 
 51     goodFriend g;
 52     g.visit();
 53     g.visit2();
 54 }
 55 
 56 int main()
 57 {
 58     test01();
 59     return 0;
 60 }