How to store custom information to an Outlook AppointmentItem

I am creating an Outlook Add-in that creates new appointments, like so:

Outlook.AppointmentItem oAppointment =
    (Outlook.AppointmentItem)outlookApp.CreateItem(O开发者_JS百科utlook.OlItemType.olAppointmentItem);
oAppointment.Subject = subject;
oAppointment.Body = description;
oAppointment.Start = startDate;
oAppointment.End = endDate;
oAppointment.Save();

Now, i want to add some custom information to those appointments, so that the application knows which appointments were created by the Add-in. Can I store that information inside the AppointmentItem, or do i have to build some sort of separate data structure that maps the appointment global id to the custom information?

Thank you.

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You could try using the UserProperties property for that.