public class NativeWIN32

    {

        public NativeWIN32()

        { }

        /* ------- using WIN32 Windows API in a C# application ------- */

        [DllImport("user32.dll", CharSet = CharSet.Auto)]

        static public extern IntPtr GetForegroundWindow(); //

        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]

        public struct STRINGBUFFER

        {

            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = )]

            public string szText;

        }

        [DllImport("user32.dll", CharSet = CharSet.Auto)]

        public static extern int GetWindowText(IntPtr hWnd, out STRINGBUFFER ClassName, int nMaxCount);

        [DllImport("user32.dll", CharSet = CharSet.Auto)]

        public static extern int SendMessage(IntPtr hWnd, int msg, int wParam, int lParam);

        [DllImport("user32.dll", CharSet = CharSet.Auto)]

        public static extern IntPtr SendMessage(IntPtr hWnd, int msg, int wParam, IntPtr lParam);

        public const int WM_SYSCOMMAND = 0x0112;

        public const int SC_CLOSE = 0xF060;

        public delegate bool EnumThreadProc(IntPtr hwnd, IntPtr lParam);

        [DllImport("user32.dll", CharSet = CharSet.Auto)]

        public static extern bool EnumThreadWindows(int threadId, EnumThreadProc pfnEnum, IntPtr lParam);

        [DllImport("user32.dll", CharSet = CharSet.Auto)]

        public static extern IntPtr FindWindowEx(IntPtr parent, IntPtr next, string sClassName, IntPtr sWindowTitle);

        /* ------- using HOTKEYs in a C# application -------

        in form load :

         bool success = RegisterHotKey(Handle, 100,     KeyModifiers.Control | KeyModifiers.Shift, Keys.J);

        in form closing :

         UnregisterHotKey(Handle, 100);

        protected override void WndProc( ref Message m )

        {

         const int WM_HOTKEY = 0x0312;  

         switch(m.Msg)

         {

          case WM_HOTKEY:

           MessageBox.Show("Hotkey pressed");

           break;

         }

         base.WndProc(ref m );

        }

        ------- using HOTKEYs in a C# application ------- */

        [DllImport("user32.dll", SetLastError = true)]

        public static extern bool RegisterHotKey(IntPtr hWnd, // handle to window

         int id,            // hot key identifier

         KeyModifiers fsModifiers,  // key-modifier options

         Keys vk            // virtual-key code

         );

        [DllImport("user32.dll", SetLastError = true)]

        public static extern bool UnregisterHotKey(IntPtr hWnd,  // handle to window

         int id      // hot key identifier

         );

        [Flags()]

        public enum KeyModifiers

        {

            None = ,

            Alt = ,

            Control = ,

            Shift = ,

            Windows =

        }

    }

        /// <summary>

        /// 注册热键

        /// </summary>

        /// <param name="c">按键</param>

        /// <param name="bCtrl">是否需要ctrl</param>

        /// <param name="bShift">是否需要shift</param>

        /// <param name="bAlt">是否需要alt</param>

        /// <param name="bWindows">是否需要win</param>

        public void SetHotKey(Keys c, bool bCtrl, bool bShift, bool bAlt, bool bWindows)

        {

            //先赋到变量

            Keys m_key = c;

            bool m_ctrlhotkey = bCtrl;

            bool m_shifthotkey = bShift;

            bool m_althotkey = bAlt;

            bool m_winhotkey = bWindows;

            //注册系统热键

            NativeWIN32.KeyModifiers modifiers = NativeWIN32.KeyModifiers.None;

            if (bCtrl)

                modifiers |= NativeWIN32.KeyModifiers.Control;

            if (bShift)

                modifiers |= NativeWIN32.KeyModifiers.Shift;

            if (bAlt)

                modifiers |= NativeWIN32.KeyModifiers.Alt;

            if (bWindows)

                modifiers |= NativeWIN32.KeyModifiers.Windows;

            NativeWIN32.RegisterHotKey(Handle, , modifiers, c);

        }

        /// <summary>

        /// 重写windows消息响应

        /// </summary>

        /// <param name="m"></param>

        protected override void WndProc(ref Message m)

        {

            const int wmHotkey = 0x0312;

            switch (m.Msg)

            {

                case wmHotkey:

                    WindowMax();

                    break;

            }

            base.WndProc(ref m);

        }