多重继承中派生类的构造函数和析构函数

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#include<iostream>using namespace std;class Base1{public:    Base1(int i)    {        cout<<"Constructing Base1 "<<i<<endl;    }};class Base2{public:    Base2(int j)    {        cout<<"Constructing Base2 "<<j<<endl;    }};class Base3{public:    Base3()    {        cout<<"Constructing Base3 *"<<endl;    }};class Derived:public Base1,public Base2,public Base3{public:    Derived(int a,int b,int c,int d):Base1(a),Base2(b),number1(c),number2(d){}private:    Base1 number1;    Base2 number2;    Base3 number3;};int main(){    Derived obj(1,2,3,4);    return 0;}

运行结果：

心得：

1、调用基类构造函数，调用顺序按照他们被继承时声明的顺序（从左向右）

2、对本类成员初始化列表中的基本类型成员和对象成员进行初始化，初始化的顺序按照他们在类中声明的顺序，对象成员初始化是自动调用对象所属类的构造函数完成。

3、执行派生类的构造函数体的内容。

对比：

#include<iostream>using namespace std;class Base1{public:    Base1(int i)    {        cout<<"Constructing Base1 "<<i<<endl;    }};class Base2{public:    Base2(int j)    {        cout<<"Constructing Base2 "<<j<<endl;    }};class Base3{public:    Base3()    {        cout<<"Constructing Base3 *"<<endl;    }};class Derived:public Base2,public Base1,public Base3{public:    Derived(int a,int b,int c,int d):Base1(a),Base2(b),number1(c),number2(d){}private:    Base1 number1;    Base2 number2;    Base3 number3;};int main(){    Derived obj(1,2,3,4);    return 0;}

运行结果：

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