The WPF class library consists of approximately 1,600 public types and more than 3,500 classes. As such, it has a considerably larger application programming interface (API) surface than either ASP.NET or Windows Forms. As you would expect from a .NET class library, all these classes can trace their ancestry back to
System.Object. In addition, most WPF classes are based on so-called base elements: the
FrameworkContentElement classes. These classes are responsible for basic item presentation and layout capabilities and are contained within the
In addition to these four base element classes, a few other important base classes drive a lot of the functionality ...