This is a demo about leveraging the databinding and templating support in Silverlight and the MVVM pattern to create a simple syntax highlighting textbox control.

The idea is to have an invisible TextBox (handling the editing) overlapping a ItemsControl that uses TextBlocks to highlight the keywords in the text. The ItemsSource property of the ItemsControl is bound to a collection property on the ViewModel, so we only need to update this collection in order to maintain the controls in sync.

In the end we'll get something like this:

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