The IDNonworkingPattern property indicates the identifier of the NonworkingPattern object to be displayed on the non-working interval. The ID property of NonworkingPattern defines the identifier of the pattern/color. The NonworkingPattern property of the NonworkingTime object gives access directly to the associated NonworkingPattern object. You can still access the NonworkingPattern object using the Item property based on the identifier. You can use the IDNonworkingPattern property to programmatically change the visual appearance of the non-working time-interval.