多继承与虚函数

#include <iostream>using namespace std;enum COLOR { Red, Green, Blue, White};class Animal{public:Animal(int);virtual ~Animal() { cout << "Animal 析构函数被调用...\n"; }virtual int GetAge() { return itsAge;}virtual void SetAge(int age) { itsAge = age; }private:int itsAge;};Animal::Animal(int age) : itsAge(age){cout << "Animal的构造函数被调用...\n";}class Horse : virtual public Animal   // 这个是虚继承，{public:Horse(COLOR color, int height, int age);virtual ~Horse(){ cout << "Horse的析构函数被调用...\n"; }virtual void Whinny() const { cout << "Whinny!.."; }virtual int GetHeight() const { return itsHeight;}virtual COLOR GetColor() const { return itsColor; }private:int itsHeight;COLOR itsColor;};Horse::Horse(COLOR color,int height, int age) : itsColor(color), itsHeight(height), Animal(age){cout << "Horse构造函数被调用...\n";}class Bird : virtual public Animal  // 这个是虚继承，{public:Bird(COLOR color,bool migrates, int age);virtual ~Bird() { cout << "Bird 的析构函数被调用...\n"; }//           鸟叫virtual void Chirp() const { cout << "Chirp...\n"; }virtual void Fly() const { cout << "I can Fly!"; }virtual bool GetMigration() const { return itsMigration;}virtual COLOR GetColor() const { return itsColor;}private:bool itsMigration;   // itsMigration 是代表的迁移，COLOR itsColor;};Bird::Bird(COLOR color, bool migrates, int age) : itsColor(color), itsMigration(migrates), Animal(age) // 构造函数， {cout << "Bird的构造函数被调用...\n";}// 多继承，就是Pegasus继承Horse而Horse又继承Animal，Pegasus继承Bird而又继承Animal，  用虚继承解决这种二义性的问题，class Pegasus : public Horse,public Bird  // 多继承，会显示二义性问题，从Horse里边继承的和从Bird里边继承的一样就是二义性问题，{public:void Chirp() const { Whinny(); }Pegasus(COLOR,int,bool,long,int);~Pegasus() { cout << "Pegasus的析构函数被调用了...\n"; }virtual long GetNumberBelievers() const{return itsNumberBelievers;}private:long itsNumberBelievers;};Pegasus::Pegasus(COLOR aColor,int height,bool migrates,long numberBelieve, int age): Horse(aColor,height,age),Bird(aColor,migrates,age),itsNumberBelievers(numberBelieve),Animal(age)   // 这个是重点，{cout << "Pegasus构造函数被调用...\n";}int main(){Pegasus *pPeg = new Pegasus(Red,5,true,80,1);pPeg->Chirp();cout << endl;pPeg->Fly();cout << endl;pPeg->Whinny();cout << endl;cout << "有" << pPeg->GetNumberBelievers() << "人相信有飞马，" << endl;// pPeg->GetColor(); // 在这里就会出现问题，不知道调用的是那一个的颜色，是Horse或Bird的，COLOR color = pPeg->Horse::GetColor();cout << "飞马的颜色：" << color << endl; // 输出的是0，代表的是red  因为COLOR是一个枚举，pPeg->Bird::GetColor();pPeg->GetAge();delete pPeg;return 0;}