C# Tutorial 9 Abstract Class Polymorphism


Get the Code Here :
Best C# Book :
Support me on Patreon :

In this part of my C# tutorial we’ll be covering Abstract Classes, Virtual Methods, Abstract Methods, Override, Base Classes, Is, As, Casting and more about Polymorphism.

For best results take notes on the cheat sheet provided above as you watch and leave any questions you have.

Thank you to Patreon supporters like the following for helping me make this video

jaryd remillard : instagram: @distant_admiration
jaryd remillard :

Nguồn: https://bdscenter.net

Xem thêm bài viết khác: https://bdscenter.net/game/


  1. Derek I just want to chime in and say that your videos are the best around – I am pivoting careers right now into c# backend dev and your tutorials have kept me productive within my team.
    What I am trying to say is keep it up, you are changing lives.

  2. I like that I can follow along with these video's because the code is zoomed in, no Indian accent either, lol., thank you

  3. Thank you for your tutorial!
    My question is, when I debug, that there is results that saying "the Circle Area is 2f".
    I do not know why it is not 50.27.

  4. Derek, thank you for sharing this. I am always interested in how other developers approach things and you are well spoken and use examples that are easy to understand. You may want to think about teaching a course on Pluralsight or one of the other code teaching sites. I have a subscription to Pluralsight and you teach better than many of the people who taught the classes i have seen on there. In any case, thanks for sharing your knowledge.

  5. greetings, could anyone guess why I seem to be getting a "cannot implicitly convert type" error msg on line #116: … new Rectangle(4,5)};
    any help appreciated

  6. Good one again. I'm learning a lot from these. I mostly program in VB, but there's a lot of demand for C# out there, so I want to know it.

  7. Great video Derek. I've learned a lot from your videos. Just noticed one thing. Shouldn't the Name property in the Shape class be protected instead of public? In the way that it is right now, one can actually name a circle object: "rectangle".

  8. Hi Derek, this is a good video. Thanks for your sharing.
    I have one question, why do we able to create an abstract class instantiate (e.g. shape[] ) ? Is it because of the content is its sub classes?
    Thanks again.

  9. Hello Derek, great video again! Just one question (I must be missing something), if abstract classes are meant to not be instantiated, what is the difference between them and static classes? Thanks

  10. "Well hello internet!" He says.. and I suddenly feel the urge to yell back at my phone, "Well hello to you too! Voice of a strange yet very knowledgeable and helpful man on the YouTube-ssssss!!!" Heh heh

  11. Is there any disadvantage of using String Interpolation ?
    Even though they make the code look better, sometimes you use them other times you don't.

  12. sup derek , i was wondering why did you make the Area method abstract why didn't you make it virtual ? or what did we get from making it abstract ?

  13. @8:35 you created an array of Shape that contains Circle and Rectangle and both are derived class. Does this mean Shape array simply hold the address for its derived objects? If that is not the case, how does the compiler knows how much memory to reserve for the array since the derived objects consume more memory and may have different sizes. To be more specific, say I declare a Shape array with a capacity of 3 then how much memory does the each element consume?

  14. Thank you for such a tutorial.
    Can we have another game/problem that is designed to apply Polymorphism, Abstract, Virtual, inheritance, base etc.? detailed implementation.

  15. where can i find more info on customizing indexed placeholders? Like the one where you used {1:f2}. I'm having trouble finding this through google, because I don't know what keywords to be searching for. I tried and failed.

  16. Hi Derek! I am thinking to learn a "hard" language. I am between Java and C#. What u think is better nowadays for jobs and doing interesting things?

    Good luck!

  17. But I already know python and pygame. My question is, what can I benefit from C#/Monogame that python/pygame wont give me. I want to be able to make desktop apps and games. What about Java, is that better than C#? Could any of these be used with python? Should i learn all three? (I already know pygame so I will probably not completely give it up, but I'm just asking about alternative tools


Please enter your comment!
Please enter your name here