Dictionary<TKey,TValue>.Key Collection. Enumerator. IEnumerator. Reset Method
Sets the enumerator to its initial position, which is before the first element in the collection.
virtual void System.Collections.IEnumerator.Reset() = System::Collections::IEnumerator::Reset;
void IEnumerator.Reset ();
Sub Reset () Implements IEnumerator.Reset
The collection was modified after the enumerator was created.
An enumerator remains valid as long as the collection remains unchanged. If changes are made to the collection, such as adding, modifying, or deleting elements, the enumerator is irrecoverably invalidated and the next call to MoveNext or IEnumerator.Reset throws an InvalidOperationException.