C# Types that accept Indexing : <p>What are all the types that have built in indexing.  For example I know ICollection and IEnumerable do not, but I'd like a list of all that do.</p>

<p>Apart from the list, if anyone can supply that, my specific problem deals with indexing all x,y points on a grid, so I'd like to access the object at x,y through an index if possible.</p>

<p>Thanks</p>
