目录

一、鸭子模拟器的实现

二、类图

三、实现鸭子抽象类

 四、定义一只绿头鸭

五、定义一只模型鸭

 六、定义飞的行为

1.定义飞的行为接口类

 2.实现 会飞 的行为

3.实现不会飞的行为

七、实现鸭子 叫 的行为

1.实现叫的接口

 2.实现鸭子 呱呱叫 的行为

 3.实现鸭子 吱吱叫 的行为

 4.实现鸭子 不会叫 的行为

 八、测试

十、完整代码实现

十一、参考资料

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摘要

  策略模式体现了 “针对接口编程，而不是针对实现编程”，如有的鸭子会叫，有的鸭子不会叫，把鸭子叫的行为委托给(delegate)给 叫 的接口类去实现，而不是在 鸭子 的类中实现。 

一、鸭子模拟器的实现

二、类图

注意:

(1)Duck "Has-a" FlyBehavior

(2)Duck "Has-a" QuackBehavior

 

三、实现鸭子抽象类

CDuck.h

#pragma once #include "FlyBehavior.h" #include "QuackBehavior.h" class CDuck { public: CDuck(void); virtual ~CDuck(void); public: void SetFlyBehavior(CFlyBehavior* pFb); void SetQuackBehavior(CQuackBehavior* pQb); public: virtual void PerformQuack(); virtual void PerformFly(); public: void Swim(); virtual void Display() = 0; protected: CFlyBehavior* m_pFlyBehavior; CQuackBehavior* m_pQuackBehavior; };

CDuck.cpp

#include "stdafx.h" #include "Duck.h" #include <iostream> #include <afxwin.h> CDuck::CDuck(void) { } CDuck::~CDuck(void) { } void CDuck::SetFlyBehavior(CFlyBehavior* pFb) { m_pFlyBehavior = pFb; } void CDuck::SetQuackBehavior(CQuackBehavior* pQb) { m_pQuackBehavior = pQb; } void CDuck::PerformQuack() { m_pQuackBehavior->quack(); } void CDuck::Swim() { AfxMessageBox(_T("All ducks float, even decoys!"), MB_OK); } void CDuck::Display() { } void CDuck::PerformFly() { m_pFlyBehavior->Fly(); }

 四、定义一只绿头鸭

CMallardDuck.h

#pragma once #include "duck.h" class CMallardDuck : public CDuck { public: CMallardDuck(void); virtual ~CMallardDuck(void); public: void Display(); };

CMallardDuck.cpp

#include "stdafx.h" #include "MallardDuck.h" #include "Quack.h" #include <afxwin.h> #include "FlyWithWings.h" CMallardDuck::CMallardDuck(void) { m_pQuackBehavior = new CQuack; //呱呱叫 m_pFlyBehavior = new CFlyWithWings;//会飞 } CMallardDuck::~CMallardDuck(void) { } void CMallardDuck::Display() { AfxMessageBox(_T("我是一直绿头鸭!"), MB_OK); }

五、定义一只模型鸭

CModelDuck.h

#pragma once #include "duck.h" class CModelDuck : public CDuck { public: CModelDuck(void); virtual ~CModelDuck(void); public: virtual void Display(); };

 CModelDuck.cpp

#include "stdafx.h" #include "ModelDuck.h" #include "Quack.h" #include "FlyNoWay.h" #include "MuteQuack.h" CModelDuck::CModelDuck(void) { m_pFlyBehavior = new CFlyNoWay; //不会飞 m_pQuackBehavior = new CMuteQuack; //不会叫 } CModelDuck::~CModelDuck(void) { } void CModelDuck::Display() { AfxMessageBox(_T("我是一只模型鸭!"), MB_OK); }

 六、定义飞的行为

1.定义飞的行为接口类

CFlyBehavior.h

#pragma once class CFlyBehavior { public: CFlyBehavior(void); ~CFlyBehavior(void); public: virtual void Fly() = 0; };

CFlyBehavior.cpp

#include "stdafx.h" #include "FlyBehavior.h" CFlyBehavior::CFlyBehavior(void) { } CFlyBehavior::~CFlyBehavior(void) { }

 2.实现 会飞 的行为

CFlyBehavior.h

#pragma once #include "flybehavior.h" class CFlyWithWings : public CFlyBehavior { public: CFlyWithWings(void); virtual ~CFlyWithWings(void); public: virtual void Fly(); };

CFlyBehavior.cpp

#include "stdafx.h" #include "FlyWithWings.h" #include <afxwin.h> CFlyWithWings::CFlyWithWings(void) { } CFlyWithWings::~CFlyWithWings(void) { } void CFlyWithWings::Fly() { AfxMessageBox(_T("我会飞!"), MB_OK); }

3.实现不会飞的行为

CFlyBehavior.h

#pragma once #include "flybehavior.h" class CFlyNoWay : public CFlyBehavior { public: CFlyNoWay(void); virtual ~CFlyNoWay(void); public: virtual void Fly(); };

 CFlyBehavior.cpp

#include "stdafx.h" #include "FlyNoWay.h" #include <iostream> #include <afxwin.h> CFlyNoWay::CFlyNoWay(void) { } CFlyNoWay::~CFlyNoWay(void) { } void CFlyNoWay::Fly() { AfxMessageBox(_T("我不会飞!"), MB_OK); }

七、实现鸭子 叫 的行为

1.实现叫的接口

CQuackBehavior,h

#pragma once class CQuackBehavior { public: CQuackBehavior(void); ~CQuackBehavior(void); public: virtual void quack() = 0; };

CQuackBehavior.cpp

#include "stdafx.h" #include "QuackBehavior.h" #include <iostream> #include <afxwin.h> CQuackBehavior::CQuackBehavior(void) { } CQuackBehavior::~CQuackBehavior(void) { }

 2.实现鸭子 呱呱叫 的行为

CQuack.h

#pragma once #include "quackbehavior.h" class CQuack : public CQuackBehavior { public: CQuack(void); virtual ~CQuack(void); public: virtual void Quack(); };

CQuack.cpp

#include "stdafx.h" #include "Quack.h" CQuack::CQuack(void) { } CQuack::~CQuack(void) { } void CQuack::Quack() { AfxMessageBox(_T("呱呱叫!"), MB_OK); }

 3.实现鸭子 吱吱叫 的行为

 CSqueak.h

#pragma once #include "quackbehavior.h" class CSqueak : public CQuackBehavior { public: CSqueak(void); virtual ~CSqueak(void); public: virtual void Quack(); };

 CSqueak.cpp

#include "stdafx.h" #include "Squeak.h" #include <iostream> #include <afxwin.h> CSqueak::CSqueak(void) { } CSqueak::~CSqueak(void) { } void CSqueak::Quack() { AfxMessageBox(_T("吱吱叫!"), MB_OK); }

 4.实现鸭子 不会叫 的行为

CMuteQuack.h

#pragma once #include "quackbehavior.h" class CMuteQuack : public CQuackBehavior { public: CMuteQuack(void); virtual ~CMuteQuack(void); public: virtual void Quack(); };

CMuteQuack.cpp 

#include "stdafx.h" #include "MuteQuack.h" #include <iostream> #include <afxwin.h> CMuteQuack::CMuteQuack(void) { } CMuteQuack::~CMuteQuack(void) { } void CMuteQuack::Quack() { AfxMessageBox(_T("不会叫!"), MB_OK); }

 八、测试

CMiniDuckSimulator.h

#include "stdafx.h" #include "MiniDuckSimulator.h" #include "Duck.h" #include "MallardDuck.h" #include "ModelDuck.h" #include "FlyRocketPowered.h" CMiniDuckSimulator::CMiniDuckSimulator(void) { } CMiniDuckSimulator::~CMiniDuckSimulator(void) { } void CMiniDuckSimulator::Test() { CDuck* mallard = new CMallardDuck; //绿头鸭 mallard->PerformQuack(); mallard->PerformFly(); // CDuck *pModel = new CModelDuck; //模型鸭 pModel->PerformFly(); pModel->SetFlyBehavior(new CFlyRocketPowered); pModel->PerformFly(); }

CMiniDuckSimulator.cpp

#pragma once class CMiniDuckSimulator { public: CMiniDuckSimulator(void); ~CMiniDuckSimulator(void); public: void Test(); };

十、完整代码实现

https://github.com/mc-liyanliang/Design-patterns/tree/master/Strategy%20Pattem

十一、参考资料

《Head First设计模式》