Difference between abstract class and interface [closed]?

When we create an interface, we are basically creating a set of methods without any implementation that must be overridden by the implemented classes. The advantage is that it provides a way for a class to be a part of two classes: one from inheritance hierarchy and one from the interface. When we create an abstract class, we are creating a base class that might have one or more completed methods but at least one or more methods are left uncompleted and declared abstract.

If all the methods of an abstract class are uncompleted then it is same as an interface. The purpose of an abstract class is to provide a base class definition for how a set of derived classes will work and then allow the programmers to fill the implementation in the derived classes. Article along with the demo project discussed Interfaces versus Abstract classes.

Try thinking of it like this: An abstract class creates an "is-a" relationship. Volkswagon is a Car. An interface creates a "can-do" relationship.

Fred can IDrive. Moreover, Fred can IDrive, but Fred is a Person.

An abstract class is class probably with some abstract methods and some non-abstract methods. They do stuff (have associated code). If a new non-abstract class, subclasses the abstract class it must implement the abstract methods.I.E.Public abstract class A { public string say } // a method with code in it public abstract string say // no implementation } public class B : A { // must implement, since it is not abstract public override string say() { return " } } Interface is more like a protocol.

A list of methods that a class implementing that interface must have. But they don't do anything. They have just method prototypes.

Public interface A { string say // no implementation (code) allowed string say // no implementation (code) allowed } public class B : A { // must implement both methods string say } string say } } Both are often confused because there is no protocol/interface in C++. So the way to simulate an interface behavior in that language is writing a pure virtual class (a class with only pure virtual functions). Class A { virtual int a() = 0; // pure virtual function (no implementation) }.

A quick google search of your question produced the following results: codeproject.com/KBecause s/abstractsvsinterfaces. Aspx social.msdn.microsoft.com/Forums/en-US/c... sadi02.wordpress.com/2008/05/08/what-is-... LOTS and LOTS of stuff out there on google about this.

I would like to hear it also here, what are people meaning. – Ragims Ragimovs Sep 3 '10 at 12:21.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.