Chapter 16 code
I recommend changing StringToTypeConverter.cs (ConvertFrom) to use:
var type = Type.GetType(typeName, true);
var type = Type.GetType(typeName);
when adapting to your own projects.
This will throw an exception when the type is not found and help catch errors in the XAML that will otherwise show up as strange reflection errors and null types.
Would have saved me a couple hours.