Classes and Objects in C#

1Understanding Classes and Objects

Hi friends, in this article we will learn about classes and objects in C#. A class is a blueprint that defines data and behaviour. An object is an actual instance created from that class. For example, an employee class can define employee details and actions. Individual employees become objects. This concept is part of Object-Oriented Programming (OOP), a programming approach that organises applications around objects. We use it to build reusable and maintainable applications.

2Think About a Car

Imagine a car manufacturing company. Every car follows a common design. The design defines properties such as colour, model and speed. It also defines actions such as Start and Stop.

This design is the class. When the company manufactures individual cars using that design, each car is an object. Each object can have its own values while sharing the same structure and behaviour.

3Explore the Main Building Blocks

1. Class

A class is a blueprint. It groups variables and methods that belong together.

2. Object

An object is an instance of a class. We create it using the new keyword.

3. Properties

Properties represent an object's data. For example, Name and Brand describe a car.

4. Methods

Methods define what an object can do. For example, Start() represents a car action.

4Create Your First Class

Let's create a Car class with two properties and one method. Then we will create two objects with different values.

using System;

class Car
{
    public string Brand { get; set; }
    public string Color { get; set; }

    public void Start()
    {
        Console.WriteLine(Brand + " is starting.");
    }
}

class Program
{
    static void Main()
    {
        Car car1 = new Car();
        car1.Brand = "Toyota";
        car1.Color = "White";

        Car car2 = new Car();
        car2.Brand = "Honda";
        car2.Color = "Black";

        Console.WriteLine(car1.Brand + " - " + car1.Color);
        car1.Start();
        Console.WriteLine(car2.Brand + " - " + car2.Color);
        car2.Start();
    }
}

5See What the Program Prints

Both objects use the same Car class, but each object has its own brand and colour.

Toyota - White
Toyota is starting.
Honda - Black
Honda is starting.

6Watch Objects Come to Life

Follow how two objects are created from one class and perform the same method with different data.

7What Have We Learned?

Classes define the structure and behaviour of objects. Objects hold their own data and can execute class methods. This is one of the most important foundations of C# application development.

• A class is a blueprint.
• An object is an instance of a class.
• Properties store data and methods define behaviour.

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