| Platform SDK: Exchange 2000 Server |
[This is preliminary documentation and subject to change.]
The Web Store provides a stock set of content classes used to identify items that are messages of some kind. The following table lists the content classes along with a brief description of each.
| Content-Classes | Description |
|---|---|
| urn:content-classes:message | The base content class for all messages. This content class defines an item that is a transmittable stream, and a set of properties that describe such an item. |
| urn:content-classes:calendarmessage | Extends the urn:content-classes:message and identifies a message that contains meeting requests, appointments, and so on. |
| urn:content-classes:reportmessage | Extends the urn:content-classes:message and identifies a message that is a report. Such messages include delivery status notifications Delivery Service Notifications (DSNs), recall messages, and mail disposition notifications. |
| urn:content-classes:dsn | Extends the urn:content-classes:reportmessage and identifies a message that is delivery status notification (DSN). |
| urn:content-classes:mdn | Extends the urn:content-classes:reportmessage and identifies a message that is mail disposition notification (MDN). |
| urn:content-classes:recallmessage | Extends the urn:content-classes:message and identifies a message that is used to recall a previously sent message. |
| urn:content-classes:recallreport | Extends the urn:content-classes:recallmessage and identifies a message that contains a report about a previously sent recall message. |
The following illustration shows the hierarchy of these classes:
|----> recallmessage -----> recallreport | message----> calendarmessage | |-------> mdn |----> reportmessage |-------> dsn
Note The recallmessage, recallreport, reportmessage, mdn, and dsn content classes identify intent or purpose of an item with that class; no additional properties are defined for these classes. The calendarmessage content class does define the additional urn:schemas:calendar:method property which is specific to these types of items.
Tip Messaging content classes are good examples of using content class to refine the intended purpose of an item in the Web Store. Content class definitions do not need to specify additional properties, if those defined by the base class are sufficient. In your applications, you can use similarly defined hierarchies of content classes for the same purpose; making the intent or purpose of various items more specific.