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public static void Win(this Window window)
        {
            //如果是全屏,則最小化
            if (window.WindowState == WindowState.Maximized)
            {
                window.Topmost = false;
                window.WindowState = WindowState.Normal;
                window.WindowStyle = WindowStyle.SingleBorderWindow;

                window.ResizeMode = ResizeMode.CanResizeWithGrip;//設定為可調整窗體大小

                //獲取視窗控制代碼 
                var handle = new WindowInteropHelper(window).Handle;
                //獲取當前顯示器螢幕
                Screen screen = Screen.FromHandle(handle);

                window.Left = (screen.Bounds.Width - window.Width) / 2;
                window.Top = (screen.Bounds.Height - window.Height) / 2;

                window.WindowState = WindowState.Minimized;
                return;
            }

            //如果是視窗,則全屏
            if (window.WindowState == WindowState.Normal)
            {
                //變成無邊窗體
                window.WindowState = WindowState.Normal;//假如已經是Maximized，就不能進入全屏，所以這裡先調整狀態
                window.WindowStyle = WindowStyle.None;
                window.ResizeMode = ResizeMode.NoResize;
                window.Topmost = true;//最大化後總是在最上面

                //獲取視窗控制代碼 
                var handle = new WindowInteropHelper(window).Handle;

                //獲取當前顯示器螢幕
                Screen screen = Screen.FromHandle(handle);

                //調整視窗最大化,全屏的關鍵程式碼就是下面3句
                window.MaxWidth = screen.Bounds.Width;
                window.MaxHeight = screen.Bounds.Height;
                window.WindowState = WindowState.Maximized;

                //解決切換應用程式的問題
                window.Activated += new EventHandler(window_Activated);
                window.Deactivated += new EventHandler(window_Deactivated);
            }

        }

        static void window_Deactivated(object sender, EventArgs e)
        {
            var window = sender as Window;
            window.Topmost = false;
        }

        static void window_Activated(object sender, EventArgs e)
        {
            var window = sender as Window;
            window.Topmost = true;
        }