How can I create a singleton IEnumerable?

Question

Does C# offer some nice method to cast a single entity of type T to IEnumerable?

The only way I can think of is something like:

Answer 1

I use

Enumerable.Repeat(entity, 1);

Answer 2

Your call to AsEnumerable() is unnecessary. AsEnumerable is usually used in cases where the target object implements IQueryable<T> but you want to force it to use LINQ-to-Objects (when doing client-side filtering on a LINQ-compatible ORM, for example). Since List<T> implements IEnumerable<T> but not IQueryable<T>, there's no need for it.

Anyway, you could also create a single-element array with your item;

IEnumerable<T> enumerable = new[] { t };

Or Enumerable.Repeat

IEnumerable<T> enumerable = Enumerable.Repeat(t, 1);

Answer 3

var entity = new T();
var singleton = Enumerable.Repeat(entity, 1);

(Although I'd probably just do var singleton = new[] { entity }; in most situations, especially if it was only for private use.)