將類的成員函數註冊為回呼函數

#include <iostream>class Object {};typedef int(Object::*SAYFUNC)(const char*);class A : public Object{public:int say(const char* msg){std::cout << "A say " << msg << std::endl;return 0;}};class B : public Object{public:int run(const char* msg){std::cout << "B run " << name << msg << std::endl;return 0;}char name[64];};class Controller {public:Controller(SAYFUNC fun, Object* target){this->fun = fun;this->target = target;}~Controller(){}void dofun(const char* msg) {// (target->*fun)(msg);(target->*fun)(msg);}private:SAYFUNC fun;Object* target;};int main(void) {A* pA = new A;Controller* pController1 = new Controller((SAYFUNC)&A::say, pA);pController1->dofun("xxx1");Controller* pController2 = new Controller((SAYFUNC)&B::run, pA /*即便是傳遞的pA指標任然可以調用B的成員函數，類似將A* 強制轉換為了 B* */);pController2->dofun("xxx2");B* pB = new B;strcpy(pB->name, "Vicky");Controller* pController3 = new Controller((SAYFUNC)&B::run, pB);pController3->dofun("xxx3");system("pause");return 0;}

 

A say xxx1
B run 妄鉿xxx2
B run Vickyxxx3
請按任意鍵繼續. . .