Hi Guys,

I'm just reading up on Abstract classes and Interfaces and although I believe I am now familiar with the concept, I am struggling to see how or why I would ever use them. Now I know that existing objects in the .NET framework already use both of these models, like Lists implementing IEnumerable etc. Thats all well and good but if I wanted something that was 'enumerable' I would just stick it in a List or Array instead of creating my own class that implemented IEnumerable. So yeah, can anyone give me some examples of when you have needed to create your own classes that either use MustInherit to create an abstract class or when you have had to create your own class that implements an interface. Also, perhaps some examples of why/when you have created your own interfaces?

Thanks
Chris