C++析构函数代码实例讲解

#include 
  
   

class A {
public:
    A() {
        std::cout << "A created!" << std::endl;
    }
    /* 析构函数为虚函数 */
    virtual ~A() {
        std::cout << "A destroyed!" << std::endl;
    }
};

class B : public A
{
public:
    B() {
        std::cout << "B created!" << std::endl;
    }
    ~B() {
        std::cout << "B destroyed!" << std::endl;
    }
};

class M {
public:
    M() {
        std::cout << "M created!" << std::endl;
    }
    /* 析构函数不为虚函数 */
    /*virtual*/ ~M() {
        std::cout << "M destroyed!" << std::endl;
    }
};

class N : public M
{
public:
    N() {
        std::cout << "N created!" << std::endl;
    }
    ~N() {
        std::cout << "N destroyed!" << std::endl;
    }
};

int main()
{
    std::cout << "-------------------------------------------------------------------" << std::endl;
    A *p1 = new B();
    delete p1;
    std::cout << "-------------------------------------------------------------------" << std::endl;
    M *p2 = new N();
    delete p2;
    return 0;
}