// functor.h
class Functor
{
public:
	virtual void operator()(const char* string)=0;  // call using operator
};


template<class SomeClass>
class SpecificFunctor : public Functor
{
	void (SomeClass::*fpt)(const char*);   // pointer to member function
	SomeClass* pt2Object;                  // pointer to object
public:
	SpecificFunctor(SomeClass* _pt2Object, void(SomeClass::*_fpt)(const char*))
	{ 
		pt2Object = _pt2Object;  fpt=_fpt; 
	}
	
	virtual void operator()(const char* string)
	{
		(*pt2Object.*fpt)(string);
	}
};


class ClassA{
public:

	ClassA(){};
	void Display(const char* text) { cout << "ClassA::Display " << text << endl; };
};



class ClassB{
public:

	ClassB(){};
	void Display(const char* text) { cout << "ClassB::Display " << text << endl; };
};








// main.cpp
#include "functor.h"
int _tmain(int argc, _TCHAR* argv[])
{
	ClassA objA;
	ClassB objB;

	//    a ) functor which encapsulates pointer to object and to member of TClassA
	SpecificFunctor<ClassA> specFuncA(&objA, &ClassA::Display);

	//    b) functor which encapsulates pointer to object and to member of TClassB
	SpecificFunctor<ClassB> specFuncB(&objB, &ClassB::Display);

	Functor* vTable[] = { &specFuncA, &specFuncB };

	(*vTable[0]) ("called!");        // via function "Call"
	(*vTable[1]) ("called!");        // via operator "()"

	return 0;
}