Abstract class vs interface C#

Abstract classes should be used primarily for objects that are closely related, whereas interfaces are best suited for providing a common functionality to unrelated classes . Interfaces are a good choice when we think that the API will not change for a while.

The short answer: An abstract class allows you to create functionality that subclasses can implement or override . An interface only allows you to define functionality, not implement it. And whereas a class can extend only one abstract class, it can take advantage of multiple interfaces.

An interface is better than a abstract class when you want multiple classes to implement that interface and when you don’t have to inherit default behavior .

4) The fourth difference between abstract class and interface in Java is that abstract class are slightly faster than interface because interface involves a search before calling any overridden method in Java.30 Haz 2018

The performance of an abstract class is fast. The performance of interface is slow because it requires time to search actual method in the corresponding class. It is used to implement the core identity of class.