What's Enumerator in an object?

Question

This line of code confuses me:

List<string> keys = new List<string>();
IDictionaryEnumerator ca = cache.GetEnumerator();
while (ca.MoveNext())
{
  keys.Add(ca.Key.ToString());
}

What is an Enumerator? Is it connected to Enumerations? I try to find a tutorial on enumerators, but without success. Hope someone will have patience to explain it to me.

possible duplicate of [Can anyone explain IEnumerable and IEnumerator to me?](http://stackoverflow.com/questions/558304/can-anyone-explain-ienumerable-and-ienumerator-to-me) — Kirk Woll, Oct 05 '10 at 17:26

score 1 · Accepted Answer · answered Oct 05 '10 at 17:23

1

You don't show what type 'cache' actually is but your code is equivalent to :

foreach(var ca in cache)  
{
   keys.Add(ca.Key.ToString();
}

foreach() uses the Enumerator as well, but cleaner through compiler-generated code.

answered Oct 05 '10 at 17:23

H H

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I see. Which one is faster? Do you know that? – sandalone Oct 06 '10 at 10:26
@askmo: If you have to ask, use neither. But these 2 are the same. – H H Oct 06 '10 at 11:07

What's Enumerator in an object?

1 Answers1