WPF TextBox Border when selected?

Question

I want to make a WPF TextBox have a DarkBlue border and thickness equal to 1. I want to make the WPF have this border ( DarkBlue, thickness set to 1 ) even when the TextBox is s

Answer 1

Check FocusVisualStyle property of the FrameworkElement object (ancestor of TextBox). It's purpose is to define style applied when an element is selected.