Difference between Encapsulation and Abstraction in OOPs (C#.NET)

Introduction:
There are 4 major properties of Object Oriented Programming (OOPs) as you know. These are

1. Abstraction
2. Encapsulation
3. Inheritance
4. Polymorphism

Among of these four properties or features we will discuss about the first two (Abstraction and Encapsulation) in this post. 

Description:

So what actually Abstraction and Encapsulation are? Lets us know with an example

Abstraction:

Abstraction is a process to abstract or hide the functionality and provide users or other programmers to use it only. Like for the method Console.WriteLine(), no one knows what actually happening behind the function calling. We  are just using it by calling and passing the arguments. This is the thing called Abstraction. 

Encapsulation:

Encapsulation means to encapsulate or put every thing into one thing and provide others to use it. Like in a shaving kit there are all the necessary kits are available. And also these kits are available as loose in market. But the shaving kit is encapsulate every other kits into a small bag and provide user to use it. 

Hope so now you have a basic idea about both of these properties, Lets see a real world example of encapsulation and abstraction.

Lets assume you have to create a method to insert an users data and pass it to other developers to use. So first create a class and add a method to insert the data into database with validation. 

There will be three fields 

1. Name 
2. Email
3. Phone number

So these inputs have to validate first and then insert into db.

First create a class with all methods

class User

{

    public bool AddUser(string name, string email, string phone)

    {

        if (ValidateUser(name, email, phone))

        {

            if (AddtoDb(name, email, phone) > 0)

            {

                return true;

            }

        }

        return false;

    }

    private bool ValidateUser(string name, string email, string phone)

    {

        // do your validation

        return true;

    }

    private int AddtoDb(string name, string email, string phone)

    {

        // Write the Db code to insert the data

        return 1;

    }

}

As you can see there are three methods are written in this User class. 

• AddUser: To call from outside the class. That is why the access modifier is public.
• validateUser: To validate the user's details. Can't access from out side the class. Its private.
• AddtoDb: To insert data into database table and again it is private, can't access from out side the class.

Now another user will just call AddUser method with parameters. And that user has no idea what is actually happening inside the method. I didn't write the code to validate and insert into db, as you can get it from others examples. We will discuss about it later. 

To call the AddUser method do like following. 

class Program

{

    static void Main(string[] args)

    {

        User objUser = new User();

        bool f = objUser.AddUser("Arka", "ark@g.com", "1234567890");

    }

}

Now come back to the main discussion.

Here we are hiding the procedure of adding data into database from other users, this is Abstraction. And putting all the three methods into one User class and provide other user to use it that is called Encapsulation. 

So procedure hiding is Abstraction and putting every necessary things into one is Encapsulation.   

Hope so you have cleared your doubt about the concept of  Encapsulation and Abstraction. 

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