Windows Presentation Foundation 4.5 Cookbook

Using an attached property

Attached properties are curious beings. There is no direct analogue to anything else in the .NET framework. The closest may be extension methods, introduced in C# 3.0. Extension methods are a way of extending a type without inheriting from it (even if that type is sealed). Attached properties are dependency properties that are defined by some type, but can be used by (almost) any other typed object. That is, they can extend a type's properties without code derivation. In this recipe, we'll see how to use an existing attached property, and in the next one we'll learn how to create a new attached property.

Getting ready

Make sure Visual Studio is up and running.

How to do it...

We'll create an application that creates a rectangle ...