Schedule items can recur in time, following a specific recurrence pattern. For example an event could be set to occur each Monday, on the third day of each month, and so on. Assign a Recurrence object to item's Recurrence property to specify the time period, pattern, and other properties for the repetition of that item in time.
Once a recurrent item is added to the Schedule of a Calendar instance, the calendar creates multiple occurrences of the item in the time period being visualized. Occasionally you will get references to these occurrences passed as arguments to the calendar events or returned by the calendar methods. Occurrences are instances of the same class as of the item that was set recurrent, however their RecurrenceState property is set to Occurrence. If a user moves a recurrent event's occurrence in the calendar, thus changing its start or end time, or changes the occurrence text, an exception is created. Exceptions are item instances whose RecurrenceState is set to Exception.
