winfrom 获取焦点控件

[dllimport("user32.dll", charset = charset.auto, callingconvention = callingconvention.winapi)]
        internal static extern intptr getfocus();
        ///获取 当前拥有焦点的控件
        private control getfocusedcontrol()
        {
            control focusedcontrol = null;
            intptr focusedhandle = getfocus();
            if (focusedhandle != intptr.zero)
            focusedcontrol = control.fromchildhandle(focusedhandle);
            return focusedcontrol;
        }

原文连接：