How to Override a Base Class Method in a Derived Class in C++?

Function overriding is a concept in object-oriented programming languages, in which a function/method of a parent class is redefined in its child class to change its behavior for the objects of the child class. In this article, we are going to learn how to override a base class function in a derived class in C++.

Override Inherited Methods in C++

In C++, you can override a base class function in a derived class by declaring a function with the same signature in the derived class. Also, ensure that the base class function is declared as virtual function to enable dynamic binding.

C++ Program to Override a Base Class Function in a Derived Class

C++

// C++ Program to Override a Base Class Function in a
// Derived Class
#include <iostream>
using namespace std;

// Base class Person
class Person {
public:
    // Virtual function to greet
    virtual void greet()
    {
        cout << "Person: Hello, there! \n";
    }
};

// Derived class AngryPerson inheriting from Person
class AngryPerson : public Person {
public:
    // Override the greet function to provide a different
    // greeting
    void greet() override
    {
        cout << "Angry Person: Hello, looser! \n";
    }
};

// Driver Code
int main()
{
    // Create objects of both classes
    Person p;
    AngryPerson ap;

    // Call the greet function for both objects
    p.greet();
    ap.greet();
    return 0;
}

Output

Person: Hello, there! 
Angry Person: Hello, looser! 

Note: It is recommended to use the override keyword to make sure that the user have not forgotten to declare the base class version of the function as virtual.