Where would you use abstract class and interface in VB.NET?

Question

Where would you use abstract class and interface in VB.NET? give also example!

Martin van Eerde · Answer

A abstract class defines a IS A relationship between two classes. A interface defines a contract you a class will implement. Generally interfaces should only have a small number of methods and be very specific. As Andrew says you should do some reading especially composition over inheritance.

Andrew Fenster · Answer

There are a few differences between abstract classes and interfaces. These will determine which is best. The most important differences: (1) An interface has no code. It simply defines a list of public methods that any implementing class must include. An abstract class on the other hand can include code. That is it can define a list of public methods and then it can also have code to implement some or all of these. So classes that inherit from the abstract class start out with a basic set of code. (2) Your class can inherit from only one class. However it can implement any number of interfaces. You should devote some time to reading about abstract classes interfaces and inheritance. A few hours of reading will do you a tremendous amount of good.