Classes and Objects

Object-Oriented Programming (OOP) is a core paradigm of C++. It allows grouping data and functions into single entities called classes.

A class acts as a blueprint, while an object is a concrete instance of that class.

Basic Syntax of a class

In C++, you use the class keyword. Unlike some other languages, in C++, class definitions must end with a semicolon ;:

#include <iostream>
#include <string>

class Player {
    // By default, all members of a class are private
private:
    std::string name;
    int score = 0;

public:
    // Public methods to access or modify private data
    void setName(std::string newName) {
        name = newName;
    }

    void addScore(int points) {
        score += points;
    }

    void display() {
        std::cout << name << " has " << score << " points!" << std::endl;
    }
};

int main() {
    Player p; // Creating an object of type Player
    p.setName("Marco");
    p.addScore(15);
    p.display();
    return 0;
}

Access Specifiers: public and private

Encapsulation consists of hiding the internal implementation details of an object and exposing only a controlled interface.

C++ manages this control using access specifiers:

• private: members are only accessible inside member functions of the class itself.
• private is the default access level for classes.
• public: members are accessible from anywhere outside the class.

Try it yourself