By default, the AllowSelectEventRect property is exLeftClick + exALTKey, which indicates that the user can select multiple events by dragging a rectangle if the user clicks and keeps the ALT key pressed. You can use the AllowSelectEvent property to change the key to allow the user select new events or you can prevent selecting any event using exDisallow value. The LayoutStartChanging( exScheduleSelectionChange) event occurs once the user is about to change the selection ( of events ), in the schedule view. The LayoutEndChanging( exScheduleSelectionChange) event occurs once the user changed the selection ( of events ), in the schedule view. The Selectable property of the event indicates whether the event can be selected at runtime. The Selected property of the Event indicates whether the current event is selected or unselected. The SelectEventStyle property indicates the way the selected events are shown. The SelectEventColor property specifies the visual appearance of the selected event. The SelectEventTextColor property specifies the foreground color of the selected event. The AllowToggleSelectKey property indicates the key to be used so the user can toggle a selected event.

You can do the same type of the selection in the calendar panel, by using the AllowSelectDateRect property.

The following screen shot shows the rectangular selection, in the schedule panel: