These classes map closely to the constructs defined in the Atom 1.0 specification, although some of the names are different.
A key feature of syndication protocols is extensibility. Both Atom 1.0 and RSS 2.0, add attributes and elements to syndication feeds that are not defined in the specifications. The Windows Communication Foundation (WCF) syndication programming model provides the following ways of working with custom attributes and extensions, loosely-typed access and deriving a new class.
Loosely Typed Access
Deriving a New Class
- Create a class to hold the extension data. In this case, create a class called MyExtension.
- Derive a class called MyExtensionItem from SyndicationItem to expose a property of type MyExtension for programmability purposes.
- Override TryParseElement in the MyExtensionItem class to instantiate a new MyExtension instance when a MyExtension is read in.
- Override WriteElementExtensions in the MyExtensionItem class to write the contents of the MyExtension property to an XML writer.
- Derive a class called MyExtensionFeed from SyndicationFeed.
- Override CreateItem in the MyExtensionFeed class to instantiate a MyExtensionItem instead of the default SyndicationItem. A series of methods are defined in SyndicationFeed and SyndicationItem that can create SyndicationLink, SyndicationCategory, and SyndicationPerson objects (for example, CreateLink, CreateCategory, and CreatePerson). All of which can be overridden to create a custom derived class.
See full details: http://msdn.microsoft.com/en-us/library/bb924494.aspx