C++学习笔记（Day12 派生类的析构函数）

• 析构函数不被继承，派生类如果需要，要自行声明析构函数。
• 声明方法与无继承关系时类的析构函数相同。
• 不需要显式地调用基类的析构函数，系统会自动隐式调用。
• 先执行派生类析构函数的函数体，再调用基类的析构函数。

#include <iostream>
using namespace std;class Base1{
public:Base1(int i){cout<< "Constructing Base1 " << i << endl;};~Base1(){cout << "Destructing Base1 " << endl;}
};
class Base2{
public:Base2(int j){cout << "Constructing Base2 " << j << endl;};~Base2(){cout << "Destructing Base2 " << endl;}
};
class Base3{
public:Base3(){cout <<"Constructing Base3 *" << endl;};~Base3(){cout << "Destructing Base3 " << endl;}
};class Derived:public Base2,public Base1,public Base3{//派生新类Derived，注意基类名的顺序
public:Derived(int a,int b,int c,int d):Base1(a),member2(d),member1(c),Base2(b){//此处的次序与构造函数的执行次序无关//注意基类名的个数与顺序，注意成员对象名的个数与顺序};
private:Base1 member1;Base2 member2;Base3 member3;
};
int main() { //主函数Derived obj(1,2,3,4);return 0;
}