.NET: Get all Outlook calendar items

Question

I've studied the docs and this is my result: I've put a time limit of one month hard-coded, but this is just an example.

public void GetAllCalendarItems()
{
    Microsoft.Office.Interop.Outlook.Application oApp = null;
    Microsoft.Office.Interop.Outlook.NameSpace mapiNamespace = null;
    Microsoft.Office.Interop.Outlook.MAPIFolder CalendarFolder = null;
    Microsoft.Office.Interop.Outlook.Items outlookCalendarItems = null;

    oApp = new Microsoft.Office.Interop.Outlook.Application();
    mapiNamespace = oApp.GetNamespace("MAPI"); ;
    CalendarFolder = mapiNamespace.GetDefaultFolder(Microsoft.Office.Interop.Outlook.OlDefaultFolders.olFolderCalendar);
    outlookCalendarItems = CalendarFolder.Items;
    outlookCalendarItems.IncludeRecurrences = true;

    foreach (Microsoft.Office.Interop.Outlook.AppointmentItem item in outlookCalendarItems)
    {
        if (item.IsRecurring)
        {
            Microsoft.Office.Interop.Outlook.RecurrencePattern rp = item.GetRecurrencePattern();
            DateTime first = new DateTime(2008, 8, 31, item.Start.Hour, item.Start.Minute, 0);
            DateTime last = new DateTime(2008, 10, 1);
            Microsoft.Office.Interop.Outlook.AppointmentItem recur = null;



            for (DateTime cur = first; cur <= last; cur = cur.AddDays(1))
            {
                try
                {
                    recur = rp.GetOccurrence(cur);
                    MessageBox.Show(recur.Subject + " -> " + cur.ToLongDateString());
                }
                catch
                { }
            }
        }
        else
        {
            MessageBox.Show(item.Subject + " -> " + item.Start.ToLongDateString());
        }
    }

}

I believe that you must Restrict or Find in order to get recurring appointments, otherwise Outlook won't expand them. Also, you must Sort by Start before setting IncludeRecurrences.

I wrote similar code, but then found the export functionality:

Application outlook;
NameSpace OutlookNS;

outlook = new ApplicationClass();
OutlookNS = outlook.GetNamespace("MAPI");

MAPIFolder f = OutlookNS.GetDefaultFolder(OlDefaultFolders.olFolderCalendar);

CalendarSharing cs = f.GetCalendarExporter();
cs.CalendarDetail = OlCalendarDetail.olFullDetails;
cs.StartDate = new DateTime(2011, 11, 1);
cs.EndDate = new DateTime(2011, 12, 31);
cs.SaveAsICal("c:\\temp\\cal.ics");

LinqPad snipped that works for me:

//using Microsoft.Office.Interop.Outlook
Application a = new Application();
Items i = a.Session.GetDefaultFolder(OlDefaultFolders.olFolderCalendar).Items;
i.IncludeRecurrences = true;
i.Sort("[Start]");
i = i.Restrict(
    "[Start] >= '10/1/2013 12:00 AM' AND [End] < '10/3/2013 12:00 AM'");


var r =
    from ai in i.Cast<AppointmentItem>()
    select new {
        ai.Categories,
        ai.Start,
        ai.Duration
        };
r.Dump();

If you need want to access the shared folder from your friend, then you can set your friend as the recipient. Requirement: his calendar must be shared first.

// Set recepient
Outlook.Recipient oRecip = (Outlook.Recipient)oNS.CreateRecipient("[email protected]");

// Get calendar folder 
Outlook.MAPIFolder oCalendar = oNS.GetSharedDefaultFolder(oRecip, Outlook.OlDefaultFolders.olFolderCalendar);

There is no need to expand recurring items manually. Just ensure you sort the items before using IncludeRecurrences.

Here is VBA example:

tdystart = VBA.Format(#8/1/2012#, "Short Date")
tdyend = VBA.Format(#8/31/2012#, "Short Date")

Dim folder As MAPIFolder
Set appointments = folder.Items

appointments.Sort "[Start]" ' <-- !!! Sort is a MUST
appointments.IncludeRecurrences = True ' <-- This will expand reccurent items

Set app = appointments.Find("[Start] >= """ & tdystart & """ and [Start] <= """ & tdyend & """")

While TypeName(app) <> "Nothing"
   MsgBox app.Start & " " & app.Subject
   Set app = appointments.FindNext
Wend

public void GetAllCalendarItems()
        {
            DataTable sample = new DataTable(); //Sample Data
            sample.Columns.Add("Subject", typeof(string));
            sample.Columns.Add("Location", typeof(string));
            sample.Columns.Add("StartTime", typeof(DateTime));
            sample.Columns.Add("EndTime", typeof(DateTime));
            sample.Columns.Add("StartDate", typeof(DateTime));
            sample.Columns.Add("EndDate", typeof(DateTime));
            sample.Columns.Add("AllDayEvent", typeof(bool));
            sample.Columns.Add("Body", typeof(string));


            listViewContacts.Items.Clear();
            oApp = new Outlook.Application();
            oNS = oApp.GetNamespace("MAPI");
            oCalenderFolder = oNS.GetDefaultFolder(Microsoft.Office.Interop.Outlook.OlDefaultFolders.olFolderCalendar);
            outlookCalendarItems = oCalenderFolder.Items;
            outlookCalendarItems.IncludeRecurrences = true;
           // DataTable sample = new DataTable();
            foreach (Microsoft.Office.Interop.Outlook.AppointmentItem item in outlookCalendarItems)
            {
                DataRow row = sample.NewRow();
                row["Subject"] = item.Subject;
                row["Location"] = item.Location;
                row["StartTime"] = item.Start.TimeOfDay.ToString();
                row["EndTime"] = item.End.TimeOfDay.ToString();
                row["StartDate"] = item.Start.Date;
                row["EndDate"] = item.End.Date;
                row["AllDayEvent"] = item.AllDayEvent;
                row["Body"] = item.Body;
                sample.Rows.Add(row);
            }
            sample.AcceptChanges();
            foreach (DataRow dr in sample.Rows)
                {
                    ListViewItem lvi = new ListViewItem(dr["Subject"].ToString());

                    lvi.SubItems.Add(dr["Location"].ToString());
                    lvi.SubItems.Add(dr["StartTime"].ToString());
                    lvi.SubItems.Add(dr["EndTime"].ToString());
                    lvi.SubItems.Add(dr["StartDate"].ToString());
                    lvi.SubItems.Add(dr["EndDate"].ToString());
                    lvi.SubItems.Add(dr["AllDayEvent"].ToString());
                    lvi.SubItems.Add(dr["Body"].ToString());



                    this.listViewContacts.Items.Add(lvi);
                }
            oApp = null;
            oNS = null;

        }