类:继承-构造和析构的顺序

#include <iostream>

//在继承体系下:
//创建对象时:先调父类构造,再调子类构造
//销毁对象时:先调子类析构,再调父类析构

class A
{
	int* p;
public:
	A()
	{
		p = new int[10];
		std::cout<<"父类构造\n";
	}
	~A()
	{
		delete [] p;
		std::cout<<"父类析构\n";
	}
};

class B : public A
{
	int* b;
public:
	B()
	{
		b = new int[20];
		std::cout<<"子类构造\n";
	}
	~B()
	{
		delete [] b;
		std::cout<<"子类析构\n";
	}
};

class C : public B
{
	int b;
public:
	C()
	{
		std::cout<<"C构造\n";
	}
	~C()
	{
		std::cout<<"C析构\n";
	}
};
void main()
{
	{
		A a;
		//父类构造
	}
	//父类析构

	std::cout<<std::endl;

	{
		B b;
		//父类构造
		//子类构造
	}	
	//子类析构
	//父类析构
	
	std::cout<<std::endl;

	{
		C c;
		//父类构造
		//子类构造
		//C构造
	}
	//C析构
	//子类析构
	//父类析构

	system("pause");

}

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转载自blog.csdn.net/weixin_43374319/article/details/83869754