title: Partially change a WPF template for a standard control
body: <p>I have a <code>TextBox</code> control placed inside my window and I would like to change its <code>Border</code>. In order to do this, I have to somehow modify the existing <code>Border</code> set by the default control template.</p>
  
  <p>Is there a way to modify only a part of a default control template (for a standard WPF control) by somehow overriding the existing objects?</p>