What interface should my service return? IQueryable, IList, IEnumerable?

Question

Imagine I have a SearchService layer that has a method to search all cars starting with a certain string;

public static class Searcher{
    public IAnInterface&l         


        

Answer 1

Always go with IEnumerable unless you have a serious reason not to. You can then implement the getter with yield return.

IQueryable is a totally different kettle of fish. Not something you'd casually implement as an alternative to a typical in-memory container.

Of the rest, there is a major different between IEnumerable and the others: it's readonly.