C++虚函数和函数指针一起使用

C++虚函数和函数指针一起使用，写起来有点麻烦。

下面贴出一份示例代码，可作参考。(需要支持C++11编译)

 #include <stdio.h>
 #include <list>
 using namespace std;

 class VirtualWithCallBack {
 public:
     using CallBack = void(VirtualWithCallBack::*)(int);

 public:
     virtual void testCallBack(int arg) = ;

     virtual CallBack getCallBack() const = ;
 };

 class VirtualWithCallBackSample1 : public VirtualWithCallBack {
 public:
     VirtualWithCallBackSample1() {
         callBack = &VirtualWithCallBack::testCallBack;
     }

 public:
     void testCallBack(int arg) override {
         printf("This is virtual call 1 : arg = %d\n", arg);
     }

     CallBack getCallBack() const override {
         return callBack;
     }

 private:
     CallBack callBack = nullptr;
 };

 class VirtualWithCallBackSample2 : public VirtualWithCallBack {
 public:
     VirtualWithCallBackSample2() {
         callBack = &VirtualWithCallBack::testCallBack;
     }

 public:
     void testCallBack(int arg) override {
         printf("This is virtual call 2 : arg = %d\n", arg);
     }

     CallBack getCallBack() const override {
         return callBack;
     }

 private:
     CallBack callBack = nullptr;
 };

 class VirtualCaller {
 public:
     void push(VirtualWithCallBack* callBack) {
         callBackList.push_back(callBack);
     }

     void run() {
         for (auto r : callBackList) {
             (r->*(r->getCallBack()))();
         }
     }

 private:
     list<VirtualWithCallBack*> callBackList;
 };

 int main() {
     VirtualCaller caller;
     caller.push(new VirtualWithCallBackSample1());
     caller.push(new VirtualWithCallBackSample2());
     caller.run();
     return ;
 }

运行结果

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