随手写了几行代码

#include "stdafx.h"
#include <iostream>
using namespace std;

class InterfaceA
{
public:
        InterfaceA();
        virtual ~InterfaceA();
        virtual void Func1() = 0;
        virtual void Func2() = 0; 
};

InterfaceA::InterfaceA(){}
InterfaceA::~InterfaceA(){}


class ComponetB : public InterfaceA
{
public:
        ComponetB();
        virtual ~ComponetB();
        virtual void Func1();
        virtual void Func2(); 
};

ComponetB::ComponetB(){cout<<"组件B创建"<<endl;}
ComponetB::~ComponetB(){cout<<"组件B析构"<<endl;}
void ComponetB::Func1(){cout<<"CompoentB::Func1 is called 
";}
void ComponetB::Func2(){cout<<"ComponetB::Func2 is called 
";} 

class ComponetC : public InterfaceA
{
public:
        ComponetC();
        virtual ~ComponetC();
        virtual void Func1();
        virtual void Func2();
};
ComponetC::ComponetC(){cout<<"组件C创建"<<endl;}
ComponetC::~ComponetC(){cout<<"组件C析构"<<endl;}
void ComponetC::Func1(){cout<<"ComponentC::Fucn1 is called 
";}
void ComponetC::Func2(){cout<<"ComponetC::Func2 is called 
";}



class IFactory
{
public:
        IFactory();
        virtual ~IFactory();
        virtual InterfaceA* CreateInstance() = 0;       
protected:
        InterfaceA* m_ptrIA;
};

IFactory::IFactory() : m_ptrIA(NULL){}
IFactory::~IFactory(){if(NULL != m_ptrIA) delete m_ptrIA; m_ptrIA = NULL;}



class FactoryB : public IFactory
{
public:
        FactoryB();
        virtual ~FactoryB();
        virtual InterfaceA* CreateInstance();
};

FactoryB::FactoryB() : IFactory(){}
FactoryB::~FactoryB(){if(NULL != m_ptrIA) delete m_ptrIA; m_ptrIA = NULL;}
InterfaceA* FactoryB::CreateInstance(){return (m_ptrIA = new ComponetB());}


class FactoryC : public IFactory
{
public:
        FactoryC();
        virtual ~FactoryC();
        virtual InterfaceA* CreateInstance();
};

FactoryC::FactoryC() : IFactory(){}
FactoryC::~FactoryC() {if(NULL != m_ptrIA) delete m_ptrIA; m_ptrIA = NULL;}
InterfaceA* FactoryC::CreateInstance(){return (m_ptrIA = new ComponetC());}



 

int _tmain(int argc, _TCHAR* argv[])
{
        IFactory* pFactory = new FactoryB();
        InterfaceA* pInterface = pFactory->CreateInstance();
        pInterface->Func1();
        cout<<endl;
        pInterface->Func2();

        cout<<endl<<endl;

        delete pFactory;

        pFactory = new FactoryC();
        pInterface = pFactory->CreateInstance();
        pInterface->Func1();
        cout<<endl;
        pInterface->Func2();

        delete pFactory;


        return 0;
}