c++之虚析构和純虚析构

#include<iostream>
using namespace std;

class Animal {
public:
    Animal() {
        cout << "Animal的构造函数调用" << endl;
    }
    /*virtual ~Animal() {
        cout << "Animal的析构函数调用" << endl;
    }*/
    //对于纯虚析构，既要有声明，也需要在类外进行实现，
    //純虚函数是不需要实现的，只需要声明
    virtual ~Animal() = 0;
    virtual void speak() = 0;
};
Animal::~Animal() {
    cout << "Animal的析构函数调用" << endl;
}
class Cat :public Animal {
public:
    string name;
    Cat(string name) {
        cout << "Cat的Cat(string name)构造函数调用" << endl;
        this->name = name;
    }
    ~Cat() {
        cout << "Cat的析构函数调用" << endl;
        this->name = name;
    }
    void speak() {
        cout << "喵喵喵" << endl;
    }
};
class Dog :public Animal {
public:
    string name;
    Dog(string name) {
        cout << "Dog的Dog(string name)构造函数调用" << endl;
        this->name = name;
    }
    ~Dog() {
        cout << "Dog的析构函数调用" << endl;
        this->name = name;
    }
    void speak() {
        cout << "汪汪汪" << endl;
    }
};

//这里必须传入地址
//父类的引用指向子类的对象，实现动态多态
void doSpeak()
{
    Animal* animal = new Cat("tom");
    //父类指针在析构时，不会调用子类中的析构函数。导致了子类中有堆区属性，出现内存泄漏；
    //解决方法，将父类析构函数声明为virtual
    animal->speak();
    delete animal;
    cout << "-----------------------" << endl;
    animal = new Dog("jack");
    animal->speak();
    delete animal;
}

int main() {
    doSpeak();
    system("pause");
    return 0;
}