EWS - Access All Shared Calendars

Question

    private void ListCalendarFolders(ref List<EBCalendar> items, int offset)
    {
        var pageSize = 100;
        var view = new FolderView(pageSize, offset, OffsetBasePoint.Beginning);
        view.PropertySet = new PropertySet(BasePropertySet.FirstClassProperties);
        view.PropertySet.Add(FolderSchema.DisplayName);
        view.PropertySet.Add(FolderSchema.EffectiveRights);

        view.Traversal = FolderTraversal.Deep;

        FindFoldersResults findFolderResults = service.FindFolders(WellKnownFolderName.MsgFolderRoot, view);
        foreach (Folder myFolder in findFolderResults.Folders)
        {
            if (myFolder is CalendarFolder)
            {
                var folder = myFolder as CalendarFolder;
                items.Add(EBCalendar.FromEWSFolder(folder));
            }
        }

        if (findFolderResults.MoreAvailable)
        {
            offset = offset + pageSize;
            ListCalendarFolders(ref items, offset);
        }
    }

How can I get it to list all the shared calendars, and how can I get it to not include the folders that have been deleted?

Answer 1

By Shared Calendars do you mean the calendars under the other calendars node in Outlook ?

If so these Items are NavLinks that are stored in the Common Views folder in a Mailbox which is under the NonIPMSubtree (root) see http://msdn.microsoft.com/en-us/library/ee157359(v=exchg.80).aspx.You can use EWS to get the NavLinks from a Mailbox and use the PidTagWlinkAddressBookEID extended property to get the X500 address of the Mailbox these Links refer to and then use Resolve Name to resolve that to a SMTP Address.Then all you need to do is Bind to that folder eg

     static Dictionary<string, Folder> GetSharedCalendarFolders(ExchangeService service, String mbMailboxname)
    {
        Dictionary<String, Folder> rtList = new System.Collections.Generic.Dictionary<string, Folder>();

        FolderId rfRootFolderid = new FolderId(WellKnownFolderName.Root, mbMailboxname);
        FolderView fvFolderView = new FolderView(1000);
        SearchFilter sfSearchFilter = new SearchFilter.IsEqualTo(FolderSchema.DisplayName, "Common Views");
        FindFoldersResults ffoldres = service.FindFolders(rfRootFolderid, sfSearchFilter, fvFolderView);
        if (ffoldres.Folders.Count == 1)
        {

            PropertySet psPropset = new PropertySet(BasePropertySet.FirstClassProperties);
            ExtendedPropertyDefinition PidTagWlinkAddressBookEID = new ExtendedPropertyDefinition(0x6854, MapiPropertyType.Binary);
            ExtendedPropertyDefinition PidTagWlinkGroupName = new ExtendedPropertyDefinition(0x6851, MapiPropertyType.String);

            psPropset.Add(PidTagWlinkAddressBookEID);
            ItemView iv = new ItemView(1000);
            iv.PropertySet = psPropset;
            iv.Traversal = ItemTraversal.Associated;

            SearchFilter cntSearch = new SearchFilter.IsEqualTo(PidTagWlinkGroupName, "Other Calendars");
            // Can also find this using PidTagWlinkType = wblSharedFolder
            FindItemsResults<Item> fiResults = ffoldres.Folders[0].FindItems(cntSearch, iv);
            foreach (Item itItem in fiResults.Items)
            {
                try
                {
                    object GroupName = null;
                    object WlinkAddressBookEID = null;

                    // This property will only be there in Outlook 2010 and beyond
                    //https://msdn.microsoft.com/en-us/library/ee220131(v=exchg.80).aspx#Appendix_A_30
                    if (itItem.TryGetProperty(PidTagWlinkAddressBookEID, out WlinkAddressBookEID))
                    {

                        byte[] ssStoreID = (byte[])WlinkAddressBookEID;
                        int leLegDnStart = 0;
                        // Can also extract the DN by getting the 28th(or 30th?) byte to the second to last byte 
                        //https://msdn.microsoft.com/en-us/library/ee237564(v=exchg.80).aspx
                        //https://msdn.microsoft.com/en-us/library/hh354838(v=exchg.80).aspx
                        String lnLegDN = "";
                        for (int ssArraynum = (ssStoreID.Length - 2); ssArraynum != 0; ssArraynum--)
                        {
                            if (ssStoreID[ssArraynum] == 0)
                            {
                                leLegDnStart = ssArraynum;
                                lnLegDN = System.Text.ASCIIEncoding.ASCII.GetString(ssStoreID, leLegDnStart + 1, (ssStoreID.Length - (leLegDnStart + 2)));
                                ssArraynum = 1;
                            }
                        }
                        NameResolutionCollection ncCol = service.ResolveName(lnLegDN, ResolveNameSearchLocation.DirectoryOnly, false);
                        if (ncCol.Count > 0)
                        {

                            FolderId SharedCalendarId = new FolderId(WellKnownFolderName.Calendar, ncCol[0].Mailbox.Address);
                            Folder SharedCalendaFolder = Folder.Bind(service, SharedCalendarId);
                            rtList.Add(ncCol[0].Mailbox.Address, SharedCalendaFolder);


                        }

                    }
                }
                catch (Exception exception)
                {
                    Console.WriteLine(exception.Message);
                }

            }
        }
        return rtList;
    }

Cheers Glen