Example of callback function and function pointer in C++

Example of callback function and function pointer in C++

How to get a function pointer in a class

Implementation code:

//A Class and B The definition of a class 
class A
{
public:
  void Test()
  {
    cout << "A::Test()" << endl;
  }
};

class B : public A
{
public:
  void Test()
  {
    cout << "B::Test()" << endl;
  }
};

// Defines a pointer to a member function of a class 
typedef void (A::*A_mFun)(void);
typedef void (B::*B_mFun)(void);



int main()
{
  //Code
  A a;
  B b;
  A_mFun pAFun = &(A::Test); //Note:Test The member function must be public, Otherwise you'll get an error 
  B_mFun pBFun = &(B::Test); //Note:Test The member function must be public, Otherwise you'll get an error 
  (a.*pAFun)();        // The output A::Test()
  (b.*pBFun)();        // The output B::Test()
  (b.*pAFun)();        // The output A::Test()

  A* pA = &a;
  B* pB = &b;
  (pA->*pAFun)();       // The output A::Test()
  (pB->*pBFun)();       // The output B::Test()
  (pB->*pAFun)();       // The output A::Test(),B* A variable can be assigned to A* variable 


  return 0;
}

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