Ok, so far the best information I have gotten regarding this topic was on this thread: EWS-API-Create-Calendar-and-Share-with-reviewer-permissions. I tried asking this question on that thread but I actually posted it as an answer so it was removed by the admins (my bad!)
DISCLAIMER: I am a sysadmin by trade and moonlight in development...so please excuse any misuse of terminology or confusions in verbage.
Also, I'm working in C# here fyi.
I have read the message protocol specs from microsoft and understand that certain extended properties need to be created on a message item to properly create a sharing invitation object I understand from the post mentioned above, I can create a message object with extended properties (SetExtendedProperty(extprop,value) to be exact). I understand that I must manually create the extended properties I'm setting using new ExtendedProperty() and populate the correct Parent GUID, HexID, and Datatype on each property. From what I can gather this is more or less a "workaround" due to there being no inherent sharing object management capabilities built into the API...
But I've ran into a snag and need some clarification...
I wanted to manually create a sharing invite (via the client, the "user" way), and then attach to the message in the Sent Items box of the user who sent the invitation. I wanted to enumerate all possible properties relative to what I need to use to build a similar object so I could use it as a template and compare my objects properties against the original invite. I can get the message fine and find many properties, but not any "special" ones. The only thing I can find that differentiate the message item is the fact that it's IPM.Sharing Item Class and that it has an attachment of sharing_metadata.xml.
But am I correct in assuming now that we can create sharing invites via the API through using extended properties, that doesn't necessarily mean we can read those properties via the API??
Everything I tried to enumerate extended properties doesn't seem to work, and always returns nothing instead of an array of extended properties. Maybe I'm not doing it right, but I wanted to ask the question before spending countless more hours trying to achieve something that's not possible.
So if I can't properly enumerate the extended properties, is there a possibiltiy of using something like ExFolders or MFCMAPI or something to get those properties???
Any thoughts/suggestions/critisisms?
Thanks!
UPDATE:
Heres the function I'm playing with to try and create a sharing invite for a users calendar folder...I've commented where I'm stuck and what I'm not completely wrapping my head around:
public void CreateCalendarSharingRequest(string folderID, string owner, string sharedToUser)
{
// LOAD OUR CUSTOM PROPERTIES
Guid PropertySetSharing = new Guid("{00062040-0000-0000-C000-000000000046}");
Guid PropertySetInternetHeaders = new Guid("{00020386-0000-0000-C000-000000000046}");
// Sharing Properties
ExtendedPropertyDefinition PidLidSharingProviderGuid = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A01, MapiPropertyType.CLSID);
ExtendedPropertyDefinition PidLidSharingProvidorName = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A02, MapiPropertyType.String);
ExtendedPropertyDefinition PidLidSharingFlavor = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A18, MapiPropertyType.Integer);
ExtendedPropertyDefinition PidLidSharingRemoteStoreUid = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A48, MapiPropertyType.String);
ExtendedPropertyDefinition PidLidSharingRemoteUid = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A06, MapiPropertyType.String);
ExtendedPropertyDefinition PidTagMessageClass = new ExtendedPropertyDefinition(0x001A, MapiPropertyType.String);
ExtendedPropertyDefinition PidTagNormalizedSubject = new ExtendedPropertyDefinition(0x0E1D, MapiPropertyType.String);
ExtendedPropertyDefinition PidTagSubjectPrefix = new ExtendedPropertyDefinition(0x003D, MapiPropertyType.String);
ExtendedPropertyDefinition PidLidSharingCapabilities = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A17, MapiPropertyType.Integer);
ExtendedPropertyDefinition PidLidSharingInitiatorEntryId = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A09, MapiPropertyType.Binary);
ExtendedPropertyDefinition PidLidSharingConfigurationUrl = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A24, MapiPropertyType.String);
ExtendedPropertyDefinition PidLidSharingInitiatorName = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A07, MapiPropertyType.String);
ExtendedPropertyDefinition PidLidSharingInitiatorSMTP = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A08, MapiPropertyType.String);
ExtendedPropertyDefinition PidLidSharingLocalType = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A14, MapiPropertyType.String);
ExtendedPropertyDefinition PidLidSharingRemoteType = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A1D, MapiPropertyType.String);
ExtendedPropertyDefinition PidLidSharingRemoteName = new ExtendedPropertyDefinition(PropertySetSharing, 0x8A05, MapiPropertyType.String);
// Internet Header Properties
ExtendedPropertyDefinition PidNameContentClass = new ExtendedPropertyDefinition(PropertySetInternetHeaders, "Content-Class", MapiPropertyType.String);
ExtendedPropertyDefinition PidNameXSharingCapabilities = new ExtendedPropertyDefinition(PropertySetInternetHeaders, "X-Sharing-Capabilities", MapiPropertyType.String);
ExtendedPropertyDefinition PidNameXSharingConfigUrl = new ExtendedPropertyDefinition(PropertySetInternetHeaders, "X-Sharing-Config-Url", MapiPropertyType.String);
ExtendedPropertyDefinition PidNameXSharingFlavor = new ExtendedPropertyDefinition(PropertySetInternetHeaders, "X-Sharing-Flavor", MapiPropertyType.String);
ExtendedPropertyDefinition PidNameXSharingLocalType = new ExtendedPropertyDefinition(PropertySetInternetHeaders, "X-Sharing-Local-Type", MapiPropertyType.String);
ExtendedPropertyDefinition PidNameXSharingRemoteName = new ExtendedPropertyDefinition(PropertySetInternetHeaders, "X-Sharing-Remote-Name", MapiPropertyType.String);
ExtendedPropertyDefinition PidNameXSharingRemoteStoreUid = new ExtendedPropertyDefinition(PropertySetInternetHeaders, "X-Sharing-Remote-Store-Uid", MapiPropertyType.String);
ExtendedPropertyDefinition PidNameXSharingRemoteType = new ExtendedPropertyDefinition(PropertySetInternetHeaders, "X-Sharing-Remote-Type", MapiPropertyType.String);
ExtendedPropertyDefinition PidNameXSharingRemoteUid = new ExtendedPropertyDefinition(PropertySetInternetHeaders, "X-Sharing-Remote-Uid", MapiPropertyType.String);
ExtendedPropertyDefinition PidNameXSharingProviderGuid = new ExtendedPropertyDefinition(PropertySetInternetHeaders, "X-Sharing-Provider-Guid", MapiPropertyType.String);
ExtendedPropertyDefinition PidNameXSharingProviderName = new ExtendedPropertyDefinition(PropertySetInternetHeaders, "X-Sharing-Provider-Name", MapiPropertyType.String);
// Bind to the web services and currently selected folder
// Get the current list of delegates for this folder
ExchangeService service = GetExchangeService();
// Create a new message
EmailMessage invitationRequest = new EmailMessage(service);
invitationRequest.Subject = "I'd like to share my calendar with you";
invitationRequest.Body = "Send by Exchange Administrator on behalf of user";
invitationRequest.From = GetSMTPAddress(owner);
invitationRequest.ItemClass = "IPM.Sharing";
invitationRequest.SetExtendedProperty(PidNameContentClass, "Sharing");
invitationRequest.SetExtendedProperty(PidTagMessageClass, "IPM.Sharing");
invitationRequest.SetExtendedProperty(PidLidSharingFlavor,0x20310); /* Indicates Invitation for a special folder */
invitationRequest.SetExtendedProperty(PidNameXSharingFlavor, "20310"); /* Text representation of SharingFlavor value */
invitationRequest.SetExtendedProperty(PidLidSharingProviderGuid, PropertySetSharing.ToString());
invitationRequest.SetExtendedProperty(PidNameXSharingProviderGuid, PropertySetSharing.ToString());
invitationRequest.SetExtendedProperty(PidLidSharingCapabilities, 0x40290); /* value for Special Folders */
invitationRequest.SetExtendedProperty(PidNameXSharingCapabilities, "40290"); /* Test representation of SharingCapabilities value */
// THIS IS WHERE IM STUCK - I understand how to set some of the properties like above, but then
// it starts needing the entryID properties for the folder being shared, etc...and I'm not entirely
// sure which properties I have to set and how many can/will be autopopulated by the transport provider
// All i wanna do is send an invite message for sharing the calendar folder from one user to another!
// Add recipient info
//invitationRequest.ToRecipients.Add(sharedToUser);
//invitationRequest.SendAndSaveCopy();
}
