Event after a Outlook Appointment was saved

Question

I am writing an Outlook Add-in and want to do something (not relevant here) with the data of an Appointment after (when) it was saved.
(i am new to Outlook-Addins)
so i found that there is an AfterWrite event where i can register a Method. And there is an ItemLoad event on Application.

so my first Efford was something like this:

private void ThisAddIn_Startup(object sender, System.EventArgs e)
{
    // ...
    this.Application.ItemLoad += 
        new Outlook.ApplicationEvents_11_ItemLoadEventHandler(atItemLoad);
}
public void atItemLoad(Object item)
{
    Outlook.AppointmentItem aitem = item as Outlook.AppointmentItem;
    if (aitem != null)
    {
        aitem.AfterWrite += 
            new Outlook.ItemEvents_10_AfterWriteEventHandler(afterWrite);
    }
}
public void afterWrite()
{
    // Who was written?
    MessageBox.Show("it was written!");
}

The problem is, that I don't know how to get to the data of the Appointment, that fired the event. Application.ItemLoad registers a function that gets an Object, that can be cast to an Appointment.
AfterWrite does not. I'd like something like this:

public void afterWrite(Outlook.AppointmentItem aitem)
{
    // do something with the data from the Appointment
    MessageBox.Show(aitem.Subject + " was written!");
}

I fear that I am researching in the totally wrong direction..

*sorry if my english is a mess - it's not my mother language

edit:

i even tried a construct like this:

private List<AppointmentEventHolder> holderList = new List<AppointmentEventHolder>();

internal class AppointmentEventHolder
{
    private Outlook.AppointmentItem aitem = null;
    public AppointmentEventHolder(Outlook.AppointmentItem item)
    {
        aitem = item;
    }

    public void onWrite()
    {
        MessageBox.Show("write: " + aitem.Subject);
    }
}

public void atItemLoad(Object item)
{
    Outlook.AppointmentItem aitem = item as Outlook.AppointmentItem;
    if (aitem != null)
    {
        AppointmentEventHolder aHolder = new AppointmentEventHolder(aitem);
        holderList.Add(aHolder);
        aitem.AfterWrite += aHolder.onWrite;
    }
}

but event doesn't get fired! i am very frustrated now

Answer 1

ok, i think i got this.
You have to register a handler on the Folder, that has your Appointments.

i read and experienced myself, that its crutial to save a reference to the objects you register an event, so i did this.
So thats the code

private Outlook.MAPIFolder _CalendarFolder = null;
private Outlook.Items _CalendarItems = null;

private void ThisAddIn_Startup(object sender, System.EventArgs e)
{
    Outlook.MAPIFolder calendarFolder =
        this.Application.ActiveExplorer().Session.GetDefaultFolder(Outlook.OlDefaultFolders.olFolderCalendar);

    // get the Termine24-Folder (if not found, create it)
    try
    {
        _CalendarFolder = calendarFolder.Folders[Constants.FOLDERNAME];
    }
    catch
    {
        _CalendarFolder = calendarFolder.Folders.Add(Constants.FOLDERNAME);
    }
    _CalendarItems = _CalendarFolder.Items;
    attachEvents();

}
public void attachEvents()
{
    _CalendarItems.ItemAdd += Item_Add;
    _CalendarItems.ItemChange += Item_Change;
    _CalendarItems.ItemRemove += Item_Remove;
}
public void Item_Add(Object item)
{
    Outlook.AppointmentItem aitem = item as Outlook.AppointmentItem;
    if (aitem != null)
    {
        MessageBox.Show("add: " + aitem.Subject);
    }
    else
    {
        MessageBox.Show("add, but no appointment");
    }
}
public void Item_Change(Object item)
{
    Outlook.AppointmentItem aitem = item as Outlook.AppointmentItem;
    if (aitem != null)
    {
        MessageBox.Show("changed: " + aitem.Subject);
    }
    else
    {
        MessageBox.Show("change, but no appointment");
    }
}
public void Item_Remove()
{
    MessageBox.Show("Item_remove");
}

to good thing is, that now I also get an event if the appointment gets drag-and-dropped in the overview.

BUT the Item_Remove still don't gets me the Object that got removed.