C++ Classes and Objects

In C++, classes and objects are fundamental concepts that support object-oriented programming (OOP). Here’s a brief overview of classes and objects in C++:

Classes:

In C++, a class is a user-defined data type that allows you to encapsulate data members and member functions into a single unit. Classes are the building blocks of object-oriented programming (OOP) and provide a way to model real-world entities and their behavior.

A class is a user-defined data type in C++ that represents a blueprint for creating objects. It encapsulates data members (variables) and member functions (methods) that operate on those data members. The general syntax for a class definition is as follows:

class ClassName {

public:

    // Data members (attributes)

    dataType member1;

    dataType member2;

    // Member functions (methods)

    returnType method1(parameters);

    returnType method2(parameters);

    // …

};

public: Access specifier that defines the visibility of the members. Members declared as “public” (access specifier)can be accessed from outside the class.

Data Members:

Data members are variables declared within the class. They represent the attributes or properties of the class. Data members can have different data types.

Member Functions:

Member functions are functions declared within the class. They define the behavior or actions associated with the class. Member functions can manipulate the data members and perform various operations.

Objects:

An object(abc ob1(ob1 is the object of class abc)) is an instance of a class, created based on the class blueprint. Objects represent real-world entities and can have their own unique data and behavior. To create an object, you use the class name followed by an object name and optional parentheses:

Here’s the syntax:

ClassName objectName; // Object creation

Example:

Here’s a simple example of a C++ class and object:

#include <iostream.h>

#include<conio.h>

// Define the class

class Circle {

public:

    // Data members

    double radius;

    // Member function to calculate area

    double calculateArea() {

        return 3.14 * radius * radius;

    }

};

void main() {

    // Create an object of the Circle class

    Circle myCircle;

    // Set the radius of the circle

    myCircle.radius = 5.0;

    // Calculate and display the area

    cout << “Area of the circle: ” << myCircle.calculateArea() << endl;

    getch();

}

In this example, the Circle class has a data member radius and a member function calculateArea(). An object myCircle is created, and its radius is set to 5.0. The area of the circle is then calculated and displayed.