Gets the normalized appointment start value which is recommended for use in interval-based appointment data source queries.
A DateTime value that is the start of the appointment.
The QueryStart and SchedulerItemBase.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 SchedulerItemBase.Start and SchedulerItemBase.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 SchedulerItemBase.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).|