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 ...

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