Calling a C++ function pointer on a specific object instance

typedef void (*EventFunction)(int nEvent);

class A
{
private:
    EventFunction handler;

public:
    void SetEvent(EventFunction func) { handler = func; }

    void EventOne() { handler(1); }
};

class B
{
private:
    A a;
public:
    B() { a.SetEvent(EventFromA); }  // What do I do here?

    void EventFromA(int nEvent) { // do stuff }
};

boost::function<int (int)> f;
X x;
f = std::bind1st(
      std::mem_fun(&X::foo), &x);
f(5); // Call x.foo(5)

class A;
class B;
typedef void (B::*EventFunction)(int nEvent)

class A
{
private:
    EventFunction handler;

public:
    void SetEvent(EventFunction func) { handler = func; }

    void EventOne(B* delegate) { ((*delegate).*handler)(1); } // note: ".*"
};

class B
{
private:
    A a;
public:
    B() { a.SetEvent(&B::EventFromA); } // note: "&::"

    void EventFromA(int nEvent) { /* do stuff */ }
};

#define CALLBACKGLUE(classname , func) static void CB_ ## func(void *obj) {static_cast< classname *>(obj)->func();}
#define CALLBACKGLUEPTR(classname , func, type) static void CB_ ## func(void *obj,type *name) {static_cast< classname *>(obj)->func(name);}
#define CALLBACKGLUEPTRPTR(classname , func, type,type2) static void CB_ ## func(void *obj,type *name,type2 *name2) {static_cast< classname *>(obj)->func(name,name2);}
#define CALLBACKGLUEPTRPTRPTR(classname , func, type,type2,type3) static void CB_ ## func(void *obj,type *name,type2 *name2,type3 *name3) {static_cast< classname *>(obj)->func(name,name2,name3);}
#define CALLBACKGLUEVAL(classname , func, type) static void CB_ ## func(void *obj,type val) {static_cast< classname *>(obj)->func(val);}

class C
{
public:
  int Method1(void) { return 3; }
  int Method2(void) { return x; }

  int x;
};

// This structure will hold a thunk to
struct CCallback
{
  C *obj;  // Instance to callback on
  int (C::*callback)(void);  // Class callback method, taking no arguments and returning int
};

int CBootstrapper(CCallback *pThunk)
{
  // Call the thunk
  return ((pThunk->obj) ->* (pThunk->callback))( /* args go here */ );
}

void DoIt(C *obj, int (C::*callback)(void))
{
  // foobar() is some C library function that takes a function which takes no arguments and returns int, and it also takes a void*, and we can't change it
  struct CCallback thunk = {obj, callback};
  foobar(&CBootstrapper, &thunk);
}

int main(void)
{
  C c;
  DoIt(&c, &C::Method1);  // Essentially calls foobar() with a callback of C::Method1 on c
  DoIt(&c, &C::Method2);  // Ditto for C::Method2
}