Home / Community & Support / Knowledge Base / RadControls for ASP.NET AJAX / Scheduler / How to validate that recurring appointment's occurrences doesn't overlap (MS Outlook doesn't allow such appointment's scheduling)

How to validate that recurring appointment's occurrences doesn't overlap (MS Outlook doesn't allow such appointment's scheduling)

Article Info

Rating: Not rated

Article information

Article relates to

RadScheduler

Created by

 Nikolay Tsenkov

Last modified

 03.04.2011

Last modified by

 Nikolay Tsenkov



DESCRIPTION

MS Outlook doesn't allow scheduling of appointments whose occurrences are overlapping. For example - the validation will not pass if you try to schedule an appointment with duration of 2 hours, which occurs every 1 hour. At the same time RadScheduler, having advanced Recurrence Editor on-board, enables users to schedule such (and a lot more complex as recurrence pattern) appointments. Although this is nice-to-have kind of feature, some times one should be able to restrict the user group of his/her project (at least because most people are familiar with Outlook) and to additionally validate for this and other custom criteria.

The problem that this article is meant to solve is - how to implement such a validation on the recurrence rule, once it's needed.



SOLUTION


C#

One can handle the AppointmentInsert event with the following handler:

protected void RadScheduler1_AppointmentInsert(object sender, AppointmentInsertEventArgs e)
{
    if (!IsValidAppointment(e.Appointment))
        e.Cancel = true;
}
This same handler should be used for AppointmentUpdate event, too.

And the validation method:
 
private bool IsValidAppointment(Appointment apt)
{
    bool isValid = true;
    if (apt.RecurrenceState == RecurrenceState.Master)
    {
        RecurrenceRule parsedRule;
        RecurrenceRule.TryParse(apt.RecurrenceRule.ToString(), out parsedRule);
        DateTime[] twoOccurrences = new DateTime[2];
 
        var enumerator = parsedRule.Occurrences.GetEnumerator();
 
        int i = 0;
        for (; i < 2; i++)
            if (enumerator.MoveNext())
                twoOccurrences[i] = enumerator.Current;
            else
                break;
 
        if (i == 2)
            isValid = !(apt.Duration > (twoOccurrences[1] - twoOccurrences[0]));
    }
 
    return isValid;
}


VB

One can handle the AppointmentInsert event with the following handler:

Protected Sub RadScheduler1_AppointmentInsert(ByVal sender As Object, ByVal e As UI.AppointmentInsertEventArgs) Handles RadScheduler1.AppointmentInsert
    If Not IsValidAppointment(e.Appointment) Then
        e.Cancel = True
    End If
 
End Sub
This same handler should be used for AppointmentUpdate event, too.

And the validation function:

Private Function IsValidAppointment(ByVal apt As Appointment) As Boolean
    Dim isValid As Boolean = True
    If apt.RecurrenceState = RecurrenceState.Master Then
        Dim parsedRule As RecurrenceRule
        RecurrenceRule.TryParse(apt.RecurrenceRule.ToString(), parsedRule)
        Dim twoOccurrences(2) As DateTime
 
        Dim enumerator As IEnumerator = parsedRule.Occurrences.GetEnumerator()
 
        Dim i As Integer = 0
        For i = 0 To 1
            If enumerator.MoveNext() Then
                twoOccurrences(i) = enumerator.Current
            Else
                Exit For
            End If
        Next
 
        If i = 2 Then
            isValid = Not (apt.Duration > (twoOccurrences(1) - twoOccurrences(0)))
        End If
    End If
 
    Return isValid
End Function

Comments

There are no comments yet.
If you'd like to comment on this KB article, please, send us a Support Ticket.
Thank you!

Please Sign In to rate this article.