C++的继承中构造和析构函数的调用顺序

实例：

#include <iostream>
using namespace std;
class parent{
public:
	parent(int a, int b, int d)
	{
		this->a = a;
		this->b = b;
		this->d = d;
		cout << "基类构造" << endl;
	}
	~parent()
	{
		cout << "基类析构" << endl;
	}
public:
	int a;
private:
	int b;
protected:
	int d;
};
class child3 : public parent
{
public:
	child3(int c, int a, int b, int d) : parent(a, b, d)
	{
		this->c = c;
		cout << "派生类构造函数" << endl;
	}
	~child3()
	{
		cout << "派生类析构函数" << endl;
	}
public:
private:
	int c;
protected:
};
int main()
{
	{
		child3 oop(1, 2, 3, 3);
	}
	system("pause");
	return 0;
}

在上述代码中，程序在执行时会先进入到基类的构造函数执行parent(int a,int b,int c)构造函数，当构造函数执行结束后打印基类构造函数，然后继续执行child3的构造函数child3(int c,int a,int b,int  d),当该构造函数执行结束后打印派生类构造函数，然后进入到派生类析构函数执行，执行完成最后执行基类析构函数，最后打印基类析构函数；

混搭情况下构造和析构函数的调用规则：

构造：先调用父类构造函数，在调用构造成员，最后调用自己的构造函数；

析构：先析构自己，在析构成员变量，最后析构父类

#include <iostream>
using namespace std;
class Grad{
public:
	Grad(int _a, int _b)
	{
		this->_a = _a;
		this->_b = _b;
		cout << "Grad 构造函数" << endl;
	}
	~Grad()
	{
		cout << "Grad析构函数" << endl;
	}
private:
	int _a;
	int _b;
};
class parent 
{
public:
	parent(int a, int b, int d) 
	{
		this->a = a;
		this->b = b;
		this->d = d;
		cout << "基类构造" << endl;
	}
	~parent()
	{
		cout << "基类析构" << endl;
	}
public:
	int a;
private:
	int b;
protected:
	int d;
};
class child3 : public parent
{
public:
	child3(int c, int a, int b, int d) : parent(a, b, d), oop1(5, 6), oop2(7,8)
	{
		this->c = c;
		cout << "派生类构造函数" << endl;
	}
	~child3()
	{
		cout << "派生类析构函数" << endl;
	}
public:
	Grad oop1;
	Grad oop2;
private:
	int c;
protected:
};
int main()
{
	{
		child3 oop(1, 2, 3, 3);
	}
	system("pause");
	return 0;
}