23种设计模式C++实例之装饰模式

装饰模式就是在不改变原有的类的情况下，给它添加功能。

#include <iostream>

using namespace std;

/*
* 装饰模式：在不改变原类和使用继承的情况下，对类进行功能的增强
* 对类a功能的增强
* */

class Car {
public:
virtual ~Car() {}
virtual void go() = 0;
};

class RunCar: public Car {
public:
virtual void go() {
cout << "car can run" << endl;
}
};

class FlyCar: public Car {
public:
FlyCar(Car* car) {
m_car = car;
}
virtual void go() {
m_car->go();
fly();
}
void fly() {
cout << "car can fly" << endl;
}
private:
Car* m_car;
};

class SwimCar: public Car {
public:
SwimCar(Car* car) {
m_car = car;
}
virtual void go() {
m_car->go();
swim();
}
void swim() {
cout << "car can swim" << endl;
}
private:
Car* m_car;
};

int main() {
Car* run = NULL;
run = new RunCar();
run->go();
cout << endl;

FlyCar* fly = new FlyCar(run);
run->go();
cout << endl;

SwimCar* swim = new SwimCar(fly);
swim->go();
cout << endl;

delete swim;
delete fly;
delete run;

return 0;
}