true if the enumerator was successfully advanced to the next element; false if the enumerator has passed the end of the collection.
Type Reason InvalidOperationException The collection was modified after the current instance was instantiated.
After an enumerator is created or after the IEnumerator.Reset method is called, an enumerator is positioned before the first element of the collection, and the first call to the IEnumerator.MoveNext method moves the enumerator over the first element of the collection.
If IEnumerator.MoveNext passes the end of the collection, the enumerator is positioned after the last element in the collection and IEnumerator.MoveNext returns false. When the enumerator is at this position, subsequent calls to IEnumerator.MoveNext also return false until IEnumerator.Reset is called.
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 IEnumerator.MoveNext or IEnumerator.Reset throws an InvalidOperationException.