.NET Framework Standard Library Annotated Reference, Volume 1: Base Class Library and Extended Numerics Library

Type Summary

						public interface IEnumerable
{
  // Methods
     IEnumerator GetEnumerator ();
}

BA It is interesting to look at how the C# foreach support works with types that implement IEnumerable. For a C# program that looks like this: foreach (int v in collection) { ... } The C# compiler generates code that looks something like this: 1: IEnumerable ie = (IEnumerable) collection; 2: IEnumerator e = ie.GetEnumerator(); 3: try { 4: while (e.MoveNext()) { 5: int v = (int) e.Current; 6: ... 7: } 8: } 9: finally { 10: if (e is IDisposable) { 11: ((IDisposable)e).Dispose(); 12: } 13: } In line 1, you see the first thing we do is cast the collection to the IEnumerable interface. Then in line 2 we get the IEnumerator and in line 4 we start iterating ...