Oct 2, 2009 · When and why should abstract classes be used? I would like to see some practical examples of their uses. Also, what is the difference between abstract classes and interfaces?

Dec 16, 2009 · When inheriting an abstract class, a concrete child class must define the abstract methods, whereas an abstract class can extend another abstract class and abstract methods …

In C#, when should you use interfaces and when should you use abstract classes? What can be the deciding factor?

For abstract methods you have to explicibly state it, yes. For virtual methods it is more complicated. If you don't state the override keyword there, the original method will become …

An abstract class is a class that is declared abstract — it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed.

Apr 25, 2017 · Abstract classes can be used to store methods in an OOP-based "library"; since the class doesn't need to be instantiated, and would make little sense for it to be, keeping …

Dec 6, 2011 · What's the point of using "abstract methods"? An abstract class cannot be instantiated, but what about the abstract methods? Are they just here to say "you have to …

An abstract class has an "is-a" type relationship with your subclasses. So for instance, you could have an abstract class Shape which has stuff any shape has (like a draw function), and then a …

Abstract Data Type (ADT) is a data type, where only behavior is defined but not implementation. Opposite of ADT is Concrete Data Type (CDT), where it contains an implementation of ADT. …

Nov 7, 2009 · An abstract data type is a model of a certain kind of data structure e.g. a Stack. A Stack has push () and pop () operations and that have well-defined behaviour. The abstract …