InvalidOperationException when editing TextBlock.Inlines from inside OnTextChanged

Question

I'm getting InvalidOperationException somewhat randomly in the following code, what's a good way to fix it?

public class ParsedTextBlock : TextBlock
{
    static ParsedTextBlock() {
        TextProperty.OverrideMetadata(typeof(ParsedTextBlock),
            new FrameworkPropertyMetadata("No Text Set",
                FrameworkPropertyMetadataOptions.AffectsMeasure | FrameworkPropertyMetadataOptions.AffectsRender,
                OnTextChanged)
            );
    }

    private static void OnTextChanged(DependencyObject obj, DependencyPropertyChangedEventArgs args)
    {
        ParsedTextBlock control = (ParsedTextBlock)obj;
        control.Inlines.Clear();
        control.Inlines.Add(new Run("test " + args.NewValue as string))
    }
}

Answer 1

I don't believe changing the text from within the text changed event would be a good idea. This would cause the event to fire recursively and eventually generate a stack overflow... how ironic :)