AppointmentItem.QueryStart Property

Gets the normalized appointment start value which is recommended for use in interval-based appointment data source queries.

Namespace: DevExpress.Xpf.Scheduling

Assembly: DevExpress.Xpf.Scheduling.v19.1.dll

Declaration

C#

public DateTime QueryStart { get; }

VB.NET

Public ReadOnly Property QueryStart As Date

Property Value

Type	Description
DateTime	A DateTime value that is the start of the appointment.

Remarks

The AppointmentItem.QueryStart and AppointmentItem.QueryEnd properties allows you to calculate the correct interval for use in a SELECT query when handling the SchedulerControl.VisibleIntervalsChanged event to fetch appointments from the data source. The use of the AppointmentItem.Start and AppointmentItem.End properties is not recommended in this situation because you can miss the appointment pattern and lose appointment exceptions.

The QueryStart property return values are dependent on the appointment type, as shown in the following table.

Appointment Type	QueryStart Value
AppointmentType.Normal	The AppointmentItem.Start value.
AppointmentType.Pattern	The Start value of the first appointment in the recurring series.
AppointmentType.ChangedOccurrence	The Start value of an original occurrence before modification (as if an occurrence is restored from the exception).
AppointmentType.DeletedOccurrence	The Start value of an original occurrence before modification (as if an occurrence is restored from the exception).