| Add | Create a new DateRangeItem, add it to the Collection, and return it to the caller. |
| Add(DateRangeCollection) | Add another collection of Date Ranges to this collection. |
| Add(T) | |
| Add(DateTime, DateTime) | Add a new Date Range to the collection by member values. |
| Add(DateTime, TimeSpan) | Add a new Date Range to the collection by Member Values. |