BCGSuite for MFC
void CBCGPCalendar::ClearSelectedDates ( BOOL  bNotify = TRUE,
BOOL  bRedraw = TRUE 

Clears all selection.

Use this function to remove all selection. If bNotify is TRUE, the calendar calls OnSelectionChanged() (which in turn sends out a notification message BCGM_CALENDAR_ON_SELCHANGED).

bNotifyIf TRUE, the calendar sends "selection changed" notification.
bRedrawIf TRUE, the calendar will be redrawn to reflect the new selection state.