New to Telerik UI for ASP.NET AJAX? Download free 30-day trial


The AppointmentUpdate event occurs just before the scheduler calls its data source to update an appointment.

AppointmentUpdate has two parameters:

  • sender is the scheduler control.

  • e is an object of type AppointmentUpdateEventArgs. It has three properties:

  • Appointment is the original appointment before any updates. Any modifications you make to this object are discarded.

  • ModifiedAppointment is the updated appointment that is about to be written to the data source. You can modify the updated appointment to change the way the updates are written to the data source.

  • Cancel is a boolean value that lets you prevent the update.


protected void RadScheduler1_AppointmentUpdate(object sender, AppointmentUpdateEventArgs e)
    e.ModifiedAppointment.End = e.ModifiedAppointment.End.AddHours(1);

Protected Sub RadScheduler1_AppointmentUpdate(ByVal sender As Object, _
      ByVal e As AppointmentUpdateEventArgs) Handles RadScheduler1.AppointmentUpdate
    e.ModifiedAppointment.End = _
End Sub

Getting recurrence rule when a recurring appointment is dragged or resized

It is a known issue that occurs in cases when a recurring Appointment is dragged or resized the recurrence rule of the ModifiedAppointment is not updated properly. It can be generated correctly by using the following code:

protected void RadScheduler1_AppointmentUpdate(object sender, AppointmentUpdateEventArgs e)
    RecurrenceRule rrule;
    if (RecurrenceRule.TryParse(e.ModifiedAppointment.RecurrenceRule, out rrule))
        rrule.Range.Start = e.ModifiedAppointment.Start;
        rrule.Range.EventDuration = e.ModifiedAppointment.End - e.ModifiedAppointment.Start;
        TimeSpan startTimeChange = e.ModifiedAppointment.Start - e.Appointment.Start;
        for (int i = 0; i < rrule.Exceptions.Count; i++)
            rrule.Exceptions[i] = rrule.Exceptions[i].Add(startTimeChange);

        e.ModifiedAppointment.RecurrenceRule = rrule.ToString();
    //here goes your custom logic for the appointment update event handler


Protected Sub RadScheduler1_AppointmentUpdate(sender As Object, e As AppointmentUpdateEventArgs)
    Dim rrule As RecurrenceRule
    If RecurrenceRule.TryParse(e.ModifiedAppointment.RecurrenceRule, rrule) Then
        rrule.Range.Start = e.ModifiedAppointment.Start
        rrule.Range.EventDuration = e.ModifiedAppointment.[End] - e.ModifiedAppointment.Start
        Dim startTimeChange As TimeSpan = e.ModifiedAppointment.Start - e.Appointment.Start
        For i As Integer = 0 To rrule.Exceptions.Count - 1
            rrule.Exceptions(i) = rrule.Exceptions(i).Add(startTimeChange)

        e.ModifiedAppointment.RecurrenceRule = rrule.ToString()
    End If
    'here goes your custom logic for the appointment update event handler

End Sub

See Also

In this article