Content Class Mappings from MAPI
Topic Last Modified: 2006-06-13
The Exchange store automatically calculates and returns a value for an item's DAV:contentclass property when the property is requested by a client using the WebDAV protocol or the Exchange OLE DB (ExOLEDB) provider, if a value has not been explicitly set. In the case of a folder, the Exchange store calculates a value using the item's PR_CONTAINER_CLASS property. In all other cases, the Exchange store uses the item's PR_MESSAGE_CLASS property. This calculation occurs, for example, when a MAPI client such as Microsoft® Outlook® first creates an item in the Exchange store and a client subsequently requests the DAV:contentclass property for the item using the WebDAV protocol or the ExOLEDB provider.
The following topics discuss the PR_MESSAGE_CLASS and PR_CONTAINER_CLASS properties and how they are mapped to a value for the item's DAV:contentclass property when necessary:
Note
The value for an item's PR_CONTAINER_CLASS or PR_MESSAGE_CLASS can be accessed through the WebDAV protocol or the Exchange OLE DB provider using the https://schemas.microsoft.com/exchange/outlookfolderclass and https://schemas.microsoft.com/exchange/outlookmessageclass properties respectively.