THECODEPROGRAM

Let's get started then.

What is Abstract Class?

Abstract classes are the base of other classes. Abstract Class contains common functions which used at other classes. Purpose of abstract classes is being base for the other classes not for deriving new classes. So you can not derive objects from abstract class.

What is abstract method?

When derive new classes from these abstract classes, we have to override functions which defined as abstract method in class. We just define the function in the class body as abstract and we will not write the function body. Abstract functions have to be overrided at the derived classes.

After project creation first I recommend you to create a folder. Clean code methodology requires to be tidied up. And so I use the folders If there are so many class files to keep them as groupped.

First Add a folder in your project and right click on the folder then add a class inside this folder. Below images you can follow how can you do this.

And

Now I want to define some properties of this class. At the below code block we defined abstract class. Below code block you will see it:

    abstract class Vehicle
    {
        //Properties of the all vehicles
        public string Owner = "";
        public string Brand = "";
        public Color Color;
        public int maxSpeed = 0;
        
    }

My properties are ready and now I want to Initialize the class and set the initial values of the variables. Adding the constructor will make the class like below. When I tried to initialize it from another class, I have to send the required initialization values first.

     abstract class Vehicle
    {
        //Properties of the all vehicles
        public string Owner = "";
        public string Brand = "";
        public Color Color;
        public int maxSpeed = 0;

        //Construction Class
        public Vehicle(string _Owner, string _Brand, Color _Color, int _maxSpeed)
        {
            //I will set all required values when initialized
            Owner = _Owner;
            Brand = _Brand;
            Color = _Color;
            maxSpeed = _maxSpeed;
        }
    }

And also if you want to update these values after initialization, you can do it just making equalization from the class where it used. Because we defined it as public and other class can reach and update them.

Also we will use the abstract methods and override methods. At the below code block we will define an abstract method, later we will call that function at our derived class. At that derived class we create a new function as protected override and the same name with the abstract function.

Below code block you will see the abstract method defining:

 abstract class Vehicle
    {
        //Properties of the all vehicles
        public string Owner = "";
        public string Brand = "";
        public Color Color;
        public int maxSpeed = 0;

        //Abstract methods
        //Abstract methods will have no body here
        public abstract void setYear();

        //Construction Class
        public Vehicle(string _Owner, string _Brand, Color _Color, int _maxSpeed)
        {
            //I will set all required values when initialized
            Owner = _Owner;
            Brand = _Brand;
            Color = _Color;
            maxSpeed = _maxSpeed;
        }
    }

Our abstract class is ready. Now we will make our Car class is derived from our abstract class and we will use it at our program.

Below code block you will see deriving the class:

    //I have created a folder named Vehicles and I have a class named Vehicle
    //I derived this class from that class

    class Car : Vehicles.Vehicle
    {
        public int tyreCount = 4;

        //We need to implement construction of he class 
        public Car(string _Owner, string _Brand, Color _Color, int _maxSpeed) : base(_Owner, _Brand, _Color, _maxSpeed)
        {
        }

        //We have to override below abstract method 
        public override void setYear()
        {
            throw new NotImplementedException();
        }

        public void setColor()
        {

        }
    }

As you can see below image we can use the properties of the upper class.

We will use these classes from main windows' class. Below code block will do it.

First we have to include our folder in our class header.

using CSharp_OOP.Vehicles;

And then we will call the class with constrctor values. below code block you can see it.

 private void Form1_Load(object sender, EventArgs e)
        {
            //Here we initialized the with the required values of the class
            Car c = new Car("Burak Hamdi TUFAN", "Mercedes", Color.Black, 280);
            //Called a function that defined at Car class
            c.setColor(Color.Yellow);
            //Bring a value of class
            MessageBox.Show("The owner of the car is : " + c.Owner);
        }

Below image you can see the output of the program

Also you we can not call abstract class in our class. Below Image you will see the error:

That is all in this article.

Have a good abstraction.

Burak Hamdi TUFAN