c# 隐藏窗口在ALT+TAB中

WPF：

#region Window styles
        [Flags]
        public enum ExtendedWindowStyles
        {
            // ...
            WS_EX_TOOLWINDOW = 0x00000080,
            // ...
        }

        public enum GetWindowLongFields
        {
            // ...
            GWL_EXSTYLE = (-20),
            // ...
        }

        [DllImport("user32.dll")]
        public static extern IntPtr GetWindowLong(IntPtr hWnd, int nIndex);

        public static IntPtr SetWindowLong(IntPtr hWnd, int nIndex, IntPtr dwNewLong)
        {
            int error = 0;
            IntPtr result = IntPtr.Zero;
            // Win32 SetWindowLong doesn't clear error on success
            SetLastError(0);

            if (IntPtr.Size == 4)
            {
                // use SetWindowLong
                Int32 tempResult = IntSetWindowLong(hWnd, nIndex, IntPtrToInt32(dwNewLong));
                error = Marshal.GetLastWin32Error();
                result = new IntPtr(tempResult);
            }
            else
            {
                // use SetWindowLongPtr
                result = IntSetWindowLongPtr(hWnd, nIndex, dwNewLong);
                error = Marshal.GetLastWin32Error();
            }

            if ((result == IntPtr.Zero) && (error != 0))
            {
                throw new System.ComponentModel.Win32Exception(error);
            }

            return result;
        }

        [DllImport("user32.dll", EntryPoint = "SetWindowLongPtr", SetLastError = true)]
        private static extern IntPtr IntSetWindowLongPtr(IntPtr hWnd, int nIndex, IntPtr dwNewLong);

        [DllImport("user32.dll", EntryPoint = "SetWindowLong", SetLastError = true)]
        private static extern Int32 IntSetWindowLong(IntPtr hWnd, int nIndex, Int32 dwNewLong);

        private static int IntPtrToInt32(IntPtr intPtr)
        {
            return unchecked((int)intPtr.ToInt64());
        }

        [DllImport("kernel32.dll", EntryPoint = "SetLastError")]
        public static extern void SetLastError(int dwErrorCode);
        #endregion

        private void image_Loaded(object sender, RoutedEventArgs e)
        {
            WindowInteropHelper wndHelper = new WindowInteropHelper(this);

            int exStyle = (int)GetWindowLong(wndHelper.Handle, (int)GetWindowLongFields.GWL_EXSTYLE);

            exStyle |= (int)ExtendedWindowStyles.WS_EX_TOOLWINDOW;

            SetWindowLong(wndHelper.Handle, (int)GetWindowLongFields.GWL_EXSTYLE, (IntPtr)exStyle);
        }

winform：

   protected override CreateParams CreateParams
        {
            get
            {
                const int WS_EX_APPWINDOW = 0x40000;
                const int WS_EX_TOOLWINDOW = 0x80;
                CreateParams cp = base.CreateParams;
                cp.ExStyle &= (~WS_EX_APPWINDOW);    // 不显示在TaskBar
                cp.ExStyle |= WS_EX_TOOLWINDOW;      // 不显示在Alt-Tab
                return cp;
            }
        }