title: Where is the implementation of IEnumerable of Collection<T>
body: <p>Suppose I have a <code>Collection&lt;string&gt;</code> and I'm using <code>GetEnumerator()</code> that returns <code>IEnumerator&lt;string&gt;</code>, where can I find the implementation of <code>IEnumerator</code> for this collection? </p>
  
  <p>On MS <a href="https://msdn.microsoft.com/en-us/library/ms132409(v=vs.110).aspx" rel="nofollow">site</a> they just say:</p>
  
  <blockquote>
    <p>Returns an enumerator that iterates through the Collection.</p>
  </blockquote>
  
  <p>But where is the class that implements <code>IEnumerator</code>?</p>