简单工厂组合策略模式_反射

#include <iostream>#include <map>using namespace std;typedef void* (*CreateClass)(int,int);#define DECLARE_CLASS(className)\static CKDynamicClass *className##dc;#define IMPLEMENT_CLASS(c,className)\CKDynamicClass* className::className##dc=\new CKDynamicClass(c,className::CreateInstance);class CClassFactory{private:map<char,CreateClass>   m_mapMethod;public:void* GetClassByType(char cType,int nFirst,int nSecond){map<char,CreateClass>::const_iterator iter;iter=m_mapMethod.find(cType);if(iter!=m_mapMethod.end())return iter->second(nFirst,nSecond);elsereturn NULL;}void RegisterMethod(char cType,CreateClass method){m_mapMethod.insert(pair<char,CreateClass>(cType,method));}static CClassFactory& GetInstance(){static CClassFactory classFactory;return classFactory;}   };class CKDynamicClass{public:CKDynamicClass(char cType,CreateClass method){CClassFactory::GetInstance().RegisterMethod(cType,method);}};class COperation{protected:int m_nFirst;int m_nSecond;public:COperation(int nFirst,int nSecond):m_nFirst(nFirst),m_nSecond(nSecond){}virtual double GetResult()=0;};class CContext{private:COperation *m_classOper;public:CContext(char cType,int nFirst,int nSecond){m_classOper=(COperation*)CClassFactory::GetInstance().GetClassByType(cType,nFirst,nSecond);}double GetResult(){double dResult=0.0;if(m_classOper!=NULL)dResult=m_classOper->GetResult();return dResult;}};class CAddOperation:public COperation{private:DECLARE_CLASS(CAddOperation)public:CAddOperation(int nFirst,int nSecond):COperation(nFirst,nSecond){}static void* CreateInstance(int nFirst,int nSecond){return new CAddOperation(nFirst,nSecond);}virtual double GetResult(){return m_nFirst+m_nSecond;}};IMPLEMENT_CLASS('+',CAddOperation)class CSubOperation:public COperation{private:DECLARE_CLASS(CSubOperation)public:CSubOperation(int nFirst,int nSecond):COperation(nFirst,nSecond){}static void* CreateInstance(int nFirst,int nSecond){return new CSubOperation(nFirst,nSecond);}virtual double GetResult(){return m_nFirst-m_nSecond;}};IMPLEMENT_CLASS('-',CSubOperation)/********扩展***************/class CMulOperation:public COperation{private:DECLARE_CLASS(CMulOperation)public:CMulOperation(int nFirst,int nSecond):COperation(nFirst,nSecond){}static void* CreateInstance(int nFirst,int nSecond){return new CMulOperation(nFirst,nSecond);}virtual double GetResult(){return m_nFirst*m_nSecond;}};IMPLEMENT_CLASS('*',CMulOperation)/************************************/int main(void){char c;cin>>c;CContext *pContext=new CContext(c,4,3);cout<<pContext->GetResult()<<endl;system("pause");return 0;}