What is the most basic class that inherits ICollection<T>

Question

I need a generic collection class which I can add to, and enumerate over. Since ICollection<T> inherits from IEnumerable<T>, the class really just needs to inherit from ICollection<T>. Is there a simple generic class in the BCL that just inherits ICollection<T> like a generic version of CollectionBase? If not, then what class comes closest?

I would guess List<T> which is what I've been using but i don't need to sequential aspect. Is there anything better (by which I mean [smaller memory footprint/faster access/simpler])? Bag would be perfect if it existed.

EDIT 1: In my particular instance, I'm .concating to another IEnumerable, querying it, and then displaying the results (in no particular order). I'm not attempting to make my own class. I've just needed to make a throwaway collection so many times, that I thought it would be useful to find the best throwaway to use. Because I feel I've done something similar so many times, I felt I should keep this question as generic as possible (no pun intended), I know better now.

EDIT 2: Thanks for everybody's answers, As @BlueRaja pointed out, any simple class is going to have about the same overhead, and thus I think I will be sticking with my original ways of using List<T>. Since they are all about the same, my silly reasons of "It's easier to type", and "I don't have to bring in yet another using" aren't such bad reasons.

Answer 1

[smaller memory footprint/faster access/simpler]

They are all going to have pretty much the same memory footprint, and if you use ICollection the interface will not change.

What really matters is which will scale best for the operations you need: Linked-list does better appending/removal (of head/tail elements), while an array-based list has random-access. There are other structures too - which you should use depends on your application.

Answer 2

You'll probably want to look into Collection<T>. It was designed for the express purpose of subclassing, as the documentation indicates:

Provides the base class for a generic collection.

Having said that, any of the collections are fine; I've inherited from List<T>, Stack<T> and so on; pick whichever one is closest to the functionality you actually need.

Answer 3

Smaller and faster all depends on what exactly you're doing and what your needs are. The only other class I might recommend is LinkedList<> which implements ICollection<>.

Answer 4

You could use Reflector to check the .NET FCL and see what classes use that collection. (There is a search feature that can be started by F3.)

You can also take a look at the C5 Library to see if a collection has already been implemented that meets your needs. Check out page 13 of the C5 Manual for the collection interface hierarchy.

Answer 5

CollectionBase existed primarily to provide a simple mechanism to create typed collections. With Generics, all collections are now typed. The vast majority of cases where extensions of CollectionBase used to be used should now be using any of the built-in collections such as List<> or LinkedList<>.

Collection<> still exists for those that need to provide a custom collection for reasons other than type (i.e., extra validation on add, or some non-standard logic). Collection<> is not nearly as commonly used as CollectionBase was and serves a much smaller need.