c++ 派生类的构造函数次序

#include <iostream>
using namespace std;
class CFatherSum         //父类Sum
{
public:
    CFatherSum(int iRec){cout<<"1,Constructing CFatherSum"<<iRec<<endl;}//构造函数成员初始化
};
class CFatherBru        //父类Bru
{
public:
    CFatherBru(int iRec){cout<<"2,Constructing CFatherBru"<<iRec<<endl;}//构造函数成员初始化
};
class CFatherObam         //父类Obam
{
public:
    //第一行用于对比默认构造
    //CFatherObam(int iRec){cout<<"3,Constructing CFatherObam"<<iRec<<endl;}//构造函数成员初始化
    CFatherObam(){cout<<"3,Constructing CFatherObam*"<<endl;}//构造函数成员初始化
};
class CSon:public CFatherSum,public CFatherBru,public CFatherObam      //继承父Sum,Bru,Obam
{
public:
    CSon(int iFirst,int iSec,int iThir,int iFor):CFatherSum(iFirst),m_bru(iFor),m_sum(iThir),CFatherBru(iSec)
    {
        //CFatherObam(iFor),m_obam(iFor)        非默认构造时,须派生构造传递构造参数
    }



private:
    CFatherSum m_sum;
    CFatherBru m_bru;
    CFatherObam m_obam;

};

//主函数
int main()
{
    CSon son(1,2,3,4);

    getchar();
    return 0;

}

结果:

结果分析:

构造参数次序先后如下:

                 1,派生类定义基类的顺序:从public CFatherSum到public CFatherBru到public CFatherObam  

                 2,派生类内成员在类中声明的顺序

CFatherSum m_sum;
CFatherBru m_bru;
CFatherObam m_obam;

延伸:析构函数次序相反,试验自行增加代码

      

原文地址:https://www.cnblogs.com/liunnis/p/4463309.html