C++ 继承 构造函数、拷贝构造函数

一、整体代码

01.cpp

#include <iostream>
using namespace std;
class ObjectB
{
public:
    ObjectB(int objb) : objb_(objb)
    {
        cout<<"ObjectB ..."<<endl;
    }
    ~ObjectB()
    {
        cout<<"~ObjectB ..."<<endl;
    }
    int objb_;
};
class ObjectD
{
public:
    ObjectD(int objd) : objd_(objd)
    {
        cout<<"ObjectD ..."<<endl;
    }
    ~ObjectD()
    {
        cout<<"~ObjectD ..."<<endl;
    }
    int objd_;
};
class Base
{
public:
    Base(int b) : b_(b), objb_(111)
    {
        cout<<"Base ..."<<endl;
    }
    Base(const Base& other) : objb_(other.objb_), b_(other.b_)
    {
	cout<<"Base ...copy"<<endl;
    }
    ~Base()
    {
        cout<<"~Base ..."<<endl;
    }
    int b_;
    ObjectB objb_;
};
class Derived : public Base
{
public:
    Derived(int b, int d) : d_(d), Base(b), objd_(222)
    {
        cout<<"Derived ..."<<endl;
    }
    Derived(const Derived& other) : d_(other.d_), objd_(other.objd_), Base(other)//调用了父类的拷贝构造函数
    {
	cout<<"Derived ...copy"<<endl;
    }
    ~Derived()//先执行方法体，再调用父类的析构函数
    {
        cout<<"~Derived ..."<<endl;
    }
    int d_;
    ObjectD objd_;
};
int main(void)
{
    Derived d(100, 200);//首先调用父类的objb_(111)，然后是父类构造函数，之后是子类的objd_(222)，最后是子类的构造函数
    //cout<<d.b_<<" "<<d.d_<<endl;
    //Base b1(100);//调用父类的构造函数
    //Base b2(b1);//调用父类拷贝构造函数
    //cout<<b2.b_<<endl;
    //Derived d2(d);//调用子类拷贝构造函数
    return 0;
}

二、运行结果
ObjectB ...

Base ...

ObjectD ...

Derived ...

~Derived ...//先析构对象

~ObjectD ...//再析构对象中的成员对象

~Base ...

~ObjectB ..