OOPs CSharp

What is Virtual keyword? Posted by: Poster This keyword indicates that a member can be overridden in a child class. It can be applied to methods, properties, indexes and events.

What is New modifiers? Posted by: Poster The new modifiers hides a member of the base class. C# supports only hide by signature.

When to use Interface over abstract class?

Posted by: Charugoel

Abstract Classes: Classes which cannot be instantiated. This means one cannot make a object of this class or in other way cannot create object by saying ClassAbs abs = new ClassAbs(); where ClassAbs is abstract class.
Abstract classes contains have one or more abstarct methods, ie method body only no implementation.
Interfaces: These are same as abstract classes only difference is we can only define method definition and no implementation.
When to use wot depends on various reasons. One being design choice.
One reason for using abstarct classes is we can code common
functionality and force our developer to use it. I can have a complete
class but I can still mark the class as abstract.
Developing by interface helps in object based communication.

What is Early binding and late binding?

Posted by: Puneet20884

Calling a non-virtual method, decided at a compile time is known as early binding. Calling a virtual method (Pure Polymorphism), decided at a runtime is known as late binding.

Is string a value type or a reference type?Why

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