鍵盤鉤子屏蔽按鍵

因爲是安裝鉤子，因此全部的鍵盤接受消息第一時間都被鉤子捕獲到，有可能出現的問題如：未屏蔽alt+f4的時候 你按alt+f4結果沒反應
這時須要在代碼判斷裏面本身寫代碼處理。如後面的判斷中本身添加退出程序代碼：

                if (kbh.vkCode == (int)Keys.F4 && (int)Control.ModifierKeys == (int)Keys.Alt)  //截獲alt+f4 
 {
　　　　　　　　　　　Application.Exit(); return 1; }

 #region 鍵盤鉤子，禁止鍵盤操做屏幕（Ctrl+Alt+Del啓動任務管理器除外）
        //委託 
        public delegate int HookProc(int nCode, int wParam, IntPtr lParam);
        static int hHook = 0;
        public const int WH_KEYBOARD_LL = 13;

        //LowLevel鍵盤截獲，若是是WH_KEYBOARD＝2，並不能對系統鍵盤截取，Acrobat Reader會在你截取以前得到鍵盤。 
        HookProc KeyBoardHookProcedure;

        //鍵盤Hook結構函數 
        [StructLayout(LayoutKind.Sequential)]
        public class KeyBoardHookStruct
        {
            public int vkCode;
            public int scanCode;
            public int flags;
            public int time;
            public int dwExtraInfo;
        }
        #region DllImport
        //設置鉤子 
        [DllImport("user32.dll")]
        public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId);
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
        //抽掉鉤子 
        public static extern bool UnhookWindowsHookEx(int idHook);
        [DllImport("user32.dll")]
        //調用下一個鉤子 
        public static extern int CallNextHookEx(int idHook, int nCode, int wParam, IntPtr lParam);

        [DllImport("kernel32.dll")]
        public static extern int GetCurrentThreadId();

        [DllImport("kernel32.dll")]
        public static extern IntPtr GetModuleHandle(string name);

        public void Hook_Start()
        {
            // 安裝鍵盤鉤子 
            if (hHook == 0)
            {
                KeyBoardHookProcedure = new HookProc(KeyBoardHookProc);

                //hHook = SetWindowsHookEx(2, 
                //            KeyBoardHookProcedure, 
                //          GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), GetCurrentThreadId()); 

                hHook = SetWindowsHookEx(WH_KEYBOARD_LL,
                          KeyBoardHookProcedure,
                        GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), 0);

                //若是設置鉤子失敗. 
                if (hHook == 0)
                {
                    Hook_Clear();
                    //throw new Exception("設置Hook失敗!"); 
                }
            }
        }

        //取消鉤子事件 
        public void Hook_Clear()
        {
            bool retKeyboard = true;
            if (hHook != 0)
            {
                retKeyboard = UnhookWindowsHookEx(hHook);
                hHook = 0;
            }
            //若是去掉鉤子失敗. 
            if (!retKeyboard) throw new Exception("UnhookWindowsHookEx failed.");
        }

        //這裏能夠添加本身想要的信息處理 
        public static int KeyBoardHookProc(int nCode, int wParam, IntPtr lParam)
        {
            if (nCode >= 0)
            {
                KeyBoardHookStruct kbh = (KeyBoardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyBoardHookStruct));
                if (kbh.vkCode == 91)  // 截獲左win(開始菜單鍵) 
                {
                    return 1;
                }
                if (kbh.vkCode == 92)// 截獲右win 
                {
                    return 1;
                }
                if (kbh.vkCode == (int)Keys.Escape && (int)Control.ModifierKeys == (int)Keys.Control) //截獲Ctrl+Esc 
                {
                    return 1;
                }
                if (kbh.vkCode == (int)Keys.F4 && (int)Control.ModifierKeys == (int)Keys.Alt)  //截獲alt+f4 
                {
　　　　　　　　　　　Application.Exit();
                    return 1;
                }
                if (kbh.vkCode == (int)Keys.Tab && (int)Control.ModifierKeys == (int)Keys.Alt) //截獲alt+tab 
                {
                    return 1;
                }
                if (kbh.vkCode == (int)Keys.Escape && (int)Control.ModifierKeys == (int)Keys.Control + (int)Keys.Shift) //截獲Ctrl+Shift+Esc 
                {
                    return 1;
                }
                if (kbh.vkCode == (int)Keys.Space && (int)Control.ModifierKeys == (int)Keys.Alt)  //截獲alt+空格 
                {
                    return 1;
                }
                if (kbh.vkCode == 241)                  //截獲F1 
                {
                    return 1;
                }
                if ((int)Control.ModifierKeys == (int)Keys.Control + (int)Keys.Alt + (int)Keys.Delete)      //截獲Ctrl+Alt+Delete 
                {
                    return 1;
                }
                //if ((int)Control.ModifierKeys == (int)Keys.Control + (int)Keys.Shift)      //截獲Ctrl+Shift 
                //{ 
                //    return 1; 
                //} 

                //if (kbh.vkCode == (int)Keys.Space && (int)Control.ModifierKeys == (int)Keys.Control + (int)Keys.Alt)  //截獲Ctrl+Alt+空格 
                //{ 
                //    return 1; 
                //} 
            }
            return CallNextHookEx(hHook, nCode, wParam, lParam);
        }

        #endregion

        private void Form1_Load(object sender, EventArgs e)
        {
            Hook_Start();
        }
        void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            Hook_Clear();
        } 
        #endregion