Pro WPF in C# 2010: Windows Presentation Foundation in .NET 4

5.2. Event Routing

As you learned in the previous chapter, many controls in WPF are content controls, and content controls can hold any type and amount of nested content. For example, you can build a graphical button out of shapes, create a label that mixes text and pictures, or put content in a specialized container to get a scrollable or collapsible display. You can even repeat this nesting process to go as many layers deep as you want.

This ability for arbitrary nesting raises an interesting question. For example, imagine you have a label like this one, which contains a StackPanel that brings together two blocks of text and an image:

<Label BorderBrush="Black" BorderThickness="1"> <StackPanel> <TextBlock Margin="3"> Image and text label</TextBlock> ...