For instance, many controls send a control color notification message (WM_CTLCOLOR or one of its variants) to their parent to allow the parent to supply a brush for painting the background of the control.

• 例如：许多控件会发送控件颜色通知消息(WM_CTLCOLOR或它的一个变体)给其父窗口以允许其父窗口来提供一个绘制控件背景的刷子。