WM_CTLCOLOR一般是由子窗口发给父窗口处理，所以edit不会收到这个消息可参看WM_CTLCOLOREDIT An edit control that is not read-only or disabled sends the WM_CTLCOLOREDIT message to its parent window when the control is about to be drawn. By responding to this message, the parent window can use the specified device context handle to set the text and background colors of the edit control.
这个消息的消息反射
An edit control that is not read-only or disabled sends the WM_CTLCOLOREDIT message to its parent window when the control is about to be drawn. By responding to this message, the parent window can use the specified device context handle to set the text and background colors of the edit control.