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

Example

using System;
using System.Collections;

namespace Samples
{
  public class IEnumeratorSample
  {
    public static void Main()
    {
      IEnumerable s = "Hello world";
      IEnumerator ie = s.GetEnumerator();
      while(ie.MoveNext())
        Console.Write(ie.Current);
      Console.WriteLine();
      ie.Reset();
      while(ie.MoveNext())
        Console.Write(ie.Current);
    }
  }
}

The output is

Hello world
Hello world