C++反射的实现

反射其实就是把创建类的方法和类的字符串名字（当然也可以是相关的信息）绑定起来，这样就可以通过输入的字符串创建对应的类。

闲话少说，上代码：

【基类：Animal】

头文件：

#pragma onceclass Animal{public: Animal(){}; virtual ~Animal(){};public: virtual void test();};typedef Animal* (*funCreateAnimal)();

源文件：

#include "Animal.h"#include <iostream>using namespace std;void Animal::test(){ cout << "Animal" << endl; char ch; cin >> ch;}

【注册用的工厂类：Zoo】

头文件：

#pragma once#include "Animal.h"#include <string>#include <map>using namespace std;// 注册宏#define DECLARE_REGISTER(class_name) \ public: \ static bool s_bRegisterFlag; \ static Animal* CreateInstance() {return new class_name();}#define IMPLEMENT_REGISTER(name, class_name) \ bool class_name::s_bRegisterFlag = \ Zoo::CreateInstance()->RegisterAnimal(name, class_name::CreateInstance);class Zoo{private: map<string, funCreateAnimal>* s_AnimalMap;public: Zoo(){s_AnimalMap = NULL;} ~Zoo(){}public: bool RegisterAnimal(string name, funCreateAnimal fun); Animal* CreateAnimal(string name);public: static Zoo* CreateInstance();};

源文件：

#include "Zoo.h"Zoo* Zoo::CreateInstance(){ static Zoo* instance = new Zoo(); return instance;}bool Zoo::RegisterAnimal(string name, funCreateAnimal fun){    if (s_AnimalMap == NULL)    {         s_AnimalMap = new map<string, funCreateAnimal>();    }    if (name == "")    {        return false;    }    if (s_AnimalMap->find(name) == s_AnimalMap->end())    {        s_AnimalMap->insert(pair<string, funCreateAnimal>(name, fun));    }        return true;}Animal* Zoo::CreateAnimal(string name){    map<string, funCreateAnimal>::const_iterator iter = s_AnimalMap->find(name);    if (iter != s_AnimalMap->end())    {        funCreateAnimal fun = iter->second;        return fun();    }    return NULL;}

【子类：Cat】

头文件：

#pragma once#include "Animal.h"#include "Zoo.h"class Cat : public Animal{DECLARE_REGISTER(Cat)public: void test();};

源文件：

#include "Cat.h"#include <iostream>using namespace std;IMPLEMENT_REGISTER("Cat", Cat)void Cat::test(void){ cout << "喵喵~~" << endl; char ch; cin >> ch;}

【测试函数】

#include "Animal.h"#include "Zoo.h"int main(){ Zoo* pZoo = Zoo::CreateInstance(); Animal *animal = NULL; animal = pZoo->CreateAnimal("Cat"); animal->test(); delete animal; animal = NULL; delete pZoo; pZoo = NULL;}