本文主要是介绍C++设计模式-Decorator，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！
意图：动态的给一个对象添加一些额外的职责。比生成子类更为灵活
UML结构图：
适用：
在不影响其他对象的情况下，以动态，透明的方式给单个对象添加职责
处理那些不可撤消的职责
当不能采用生成子类的方式进行扩充时
// test.h 
/**/ // class Component 
{
public:
Component(){} virtual ~Component(){} //纯虚函数 virtual void Operation() = 0;
} ; // 抽象基类，维护一个指向Component对象的指针 class Decorator : public Component {public: Decorator(Component* pComponent) : m_pComponent(pComponent){} virtual ~Decorator();protected: Component* m_pComponent;} ; // 派生自Component，需要给他动态添加职责 class ConCreateComponent : public Component {public: ConCreateComponent(){} virtual ~ConCreateComponent(){} virtual void Operation();} ; // 派生自Decorator,为ConCreateComponent动态添加职责 class ConCreateDecorator : public Decorator {public: ConCreateDecorator(Component* pComponent) : Decorator(pComponent){} virtual ~ConCreateDecorator(){} virtual void Operation();private: void AddedBehavior(); //动态添加的职责} ;
// test.cpp : Defines the entry point for the console application.//#include "stdafx.h"#include < iostream > #include "test.h"//Decorator::~Decorator(){ delete m_pComponent; m_pComponent = NULL;}void ConCreateComponent::Operation(){ std::cout < < "Operation of ConCreateComponent\n";}void ConCreateDecorator::Operation(){ m_pComponent- > Operation(); AddedBehavior();}void ConCreateDecorator::AddedBehavior(){ std::cout < < "AddedBehavior of ConCreateDecorator\n";}//int main(int argc, char* argv[]){ Component* Pcomponent = new ConCreateComponent; //用这个对象去初始化一个Decorator对象 //通过多态调用动态添加了职责 Decorator* pDecorator = new ConCreateDecorator(Pcomponent); pDecorator- > Operation(); delete pDecorator; system("pause"); return 0;}这篇关于C++设计模式-Decorator的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！
