Classes

Class #

Class is a core building block of object-oriented programming.

An application consists of various classes that interact with each other through objects.


A class has two fundamental components, data and behavior.

  • Data is represented by fields.
  • Behavior is represented by methods.

Each fields or methods have an access modifier that controls its visibility. It defines whether they can be accessed from other code.

public class Person {
    public string Name;
    public void Greetings() {
        Console.WriteLine($"Hi, I'm {Name}");
    }
}

Class is nothing but a blueprint for creating objects.

You need to create an instance of class which is called object.

It can be done by using the new keyword.

var p1 = new Person();
p1.Name = "John";
// output: Hi, I'm John
p1.Greetings();

Person p2 = new Person();
p2.Name = "David";
// output: Hi, I'm David
p2.Greetings();

The static class is used to represents that the concept is a singleton object.

The static class is not allowed to create objects, It can only contain static fields and methods.

  • Singleton object: an object that can only be instantiated once.
  • The WriteLine method is a static member of Console class.
public static class Console {
    public static void WriteLine(){
        Out.WriteLine();
    }
}