C++派生类构造函数实战

╰+哭是因爲堅強的太久メ 2021-09-19 04:48 393阅读 0赞

**一 代码**

#include<iostream>
    #include<string>
    using namespace std;
    class CStudent{//声明基类Student
    public:
       CStudent(int n,string nam,char s){//基类构造函数
          num=n;
          name=nam;
          sex=s;
       }
       ~CStudent(){} //基类析构函数
    protected: //保护部分
       int num;
       string name;
       char sex ;
    };
    class CStudent1: public CStudent{//声明派生类Student1
    public : //派生类的公用部分
       CStudent1 (int n,string nam,char s,int a,string ad): CStudent (n,nam,s){//派生类构造函数
          age=a; //在函数体中只对派生类新增的数据成员初始化
          addr=ad;
       }
       void show(){
          cout<<"num: "<<num<<endl;
          cout<<"name: "<<name<<endl;
          cout<<"sex: "<<sex<<endl;
          cout<<"age: "<<age<<endl;
          cout<<"address: "<<addr<<endl<<endl;
       }
       ~CStudent1(){ } //派生类析构函数
    private : //派生类的私有部分
       int age;
       string addr;
    };
    int main(){
       CStudent1 stud1(10010,"Wang-li",'f',19,"115 Beijing Road,Shanghai");
       CStudent1 stud2(10011,"Zhang-fun",'m',21,"213 Shanghai Road,Beijing");
       stud1.show(); //输出第一个学生的数据
       stud2.show(); //输出第二个学生的数据
       return 0;
    }

**二 运行**

[root@localhost charpter02]# g++ 0226.cpp -o 0226
    [root@localhost charpter02]# ./0226
    num: 10010
    name: Wang-li
    sex: f
    age: 19
    address: 115 Beijing Road,Shanghai
    
    num: 10011
    name: Zhang-fun
    sex: m
    age: 21
    address: 213 Shanghai Road,Beijing

**三 说明**

实战中，类CStudent1继承了CStudent。类CStudent1比基类新增了两个数据成员。基类CStudent有自己带参构造函数，而派生类的构造函数，只须对派生类新增数据成员初始化，不过需要把基类的参数也给带进去。