Can abstract classes have implementation in c#?

Question

The compiler doesn't seem to mind it so far but I just wanted to double check whether I'm setting myself up for failure in any way by implementing certain methods in my abstract class.

Answer 1

An abstract class usually has one or more abstract method. So yes it can have some method implemented. The goal is to force the user to implement these methods to have an object working. Sometimes abstract classes are used to provide a 'base' implementation of some interfaces, leaving the final user to specify just the key methods. You can also have an abstract class without any abstract method: in this case you are asserting you must derive from that class in order to use it.

Answer 2

It's common to have some implementation in abstract classes.

If there is no implementation at all, consider using an interface instead of an abstract class.

Answer 3

Perfectly fine to implement some methods and leave others abstract.

If all methods had to be abstract, you might as well use an interface for it.