C++ 多继承基类析构虚函数

Demo:

class Animal
{
public:
    Animal()
    {
        cout << "animal..." << endl;
    }
    virtual ~Animal()
    {
        cout << "~animal..." << endl;
    }

    virtual void ShowAnimal() = 0;
};

class Cat
{
public:
    Cat()
    {
        cout << "Cat..." << endl;
    }
    virtual ~Cat()
    {
        cout << "~Cat..." << endl;
    }

    virtual void ShowCat() = 0;
};

class Tiger :public Animal, public Cat
{
public:
    Tiger()
    {
        cout << "Tiger..." << endl;
    }
    ~Tiger()
    {
        cout << "~Tiger..." << endl;
    }

    void ShowAnimal() override
    {
        cout << "老虎是动物..." << endl;
    }

    void ShowCat() override
    {
        cout << "老虎是猫科类..." << endl;
    }

    void ShowTiger()
    {
        cout << '\n';
        cout << "老虎是什么？" << endl;
        ShowAnimal();
        ShowCat();
        cout << '\n';
    }
};


int main()
{
    Cat *cat = new Tiger();
    Tiger *tiger = dynamic_cast<Tiger *>(cat);
    tiger->ShowTiger();
    delete cat;

    system("pause");
    return EXIT_SUCCESS;
}

输出：

animal...
Cat...
Tiger...

老虎是什么？
老虎是动物...
老虎是猫科类...

~Tiger...
~Cat...
~animal...

可见delete cat;时，两个基类都被析构了。