What do you mean by the "header of a winform"?
If you're referring to the title bar, then it's possible but messy...
you'd have to override WM_NCPAINT, which requires you to draw *all*
non-client areas (title bar, icon, minimize/maximize/close buttons, and
all resize borders). And Windows will sometimes randomly repaint parts
of the title bar without notifying you. Not for the faint of heart.
