Getting extended property from Exchange/Outlook appointment

Question

I add an extended property in this way:

ExtendedPropertyDefinition ep = new ExtendedPropertyDefinition(DefaultExtendedPropertySet.CalendarAssistant, "AppointmentID", MapiPropertyType.Integer);
Appointment newApp = new Appointment(service);
newapp.SetExtendedProperty(ep, appID);
newApp.Save(SendInvitationsMode.SendToNone);

All is good. The appointment shows up in Outlook as expected.

Later I tried to search through all Outlook appointment with an AppointmentID assigned by:

List<SearchFilter> filters = new List<SearchFilter>();
filters.Add(new SearchFilter.Exists(ep));
filters.Add(new SearchFilter.IsLessThan(AppointmentSchema.Start, DateTime.Now.AddDays(60)));
filters.Add(new SearchFilter.IsGreaterThanOrEqualTo(AppointmentSchema.Start, DateTime.Today));
FindItemsResults<Item> allOutlookAppt = service.FindItems(WellKnownFolderName.Calendar, new SearchFilter.SearchFilterCollection(LogicalOperator.And, filters.ToArray()), viewFind);

allOutlookAppt returns the expected collection (calendar entries with AppointmentID set). However I could not retrieve the AppointmentID by this code:

foreach (var a in allOutlookAppt) // contains correct calendar entries!
{
    object oid;
    if (a.TryGetProperty(ep, out oid))
    {
    // a.TryGetProperty is always false, oid is always null thus never enter here!
    }
}

What did I do wrong?

Edit: I tried a.ExtendedProperties.Count and it actually returns 0.

elty123 elty123 · Accepted Answer · 2015-01-28T19:50:50

After googling a bit I have to add this before searching the calendar

viewFind.PropertySet = new PropertySet(ep);

Getting extended property from Exchange/Outlook appointment

1 Answers