C++继承和派生

C++继承和派生

#include <iostream>

using namespace std;

class Person
{
public:
    Person(){ age = 30;}
    void display()
    {
        cout << "Person age :" << age << endl;
    }

private:
    int age;
};

class Father:public Person
{
public:
    Father(){ f_age = 50;}
//    void display()
//    {
//        cout << "Father f_age :" << f_age << endl;
//    }

private:
    int f_age;
};


int main()
{
    cout << "Hello World!" << endl;

    Person p;
    p.display();

    Father fa;
    fa.display();

    return 0;
}

派生类变量和函数覆盖基类

#include<iostream>
using namespace std;

class basic
{
public:
    void setx(int a){x = a;}
    void sety(int b){y = b;}
    int getx(){return x;}
    int gety(){return y;}
private:
    int x;
    int y;
};

class derived : public basic
{
public:
    void setx(char *a){x = a;}
    char* getx(){return x;}
private:
    char * x;
};

int main()
{
    derived d1;
    d1.setx("class");   //OK
    //d1.setx(50);        //compile error
    d1.basic::setx(50); //OK
    return 0;
}