winform键盘全局与线程Hook

定义数据结构

        /// <summary>
        /// 声明键盘钩子的封送结构类型
        /// </summary>
        [StructLayout(LayoutKind.Sequential)]
        public class KeyboardHookStruct
        {
            public int vkCode;//表示一个1到254间的虚拟键盘码
            public int scanCode;//表示硬件扫描码
            public int flags;
            public int time;
            public int dwExtraInfo;
        }

声明Hook相关方法

        //使用WINDOWS API函数代替获取当前实例的函数,防止钩子失效
        [DllImport("kernel32.dll")]
        public static extern IntPtr GetModuleHandle(string lpModuleName);
        //安装钩子
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
        public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId);
        //下一个钩子
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
        public static extern int CallNextHookEx(int idHook, int nCode, Int32 wParam, IntPtr lParam);
        //卸载钩子
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
        public static extern bool UnhookWindowsHookEx(int idHook);
        // 取得当前线程编号（线程钩子需要用到）
        [DllImport("kernel32.dll")]
        static extern int GetCurrentThreadId();

Hook拦截方法

全局Hook

        private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)
        {
            if ((nCode >= 0) && (OnKeyDownEvent != null || OnKeyUpEvent != null || OnKeyPressEvent != null))
            {
                KeyboardHookStruct MyKBHookStruct = (KeyboardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyboardHookStruct));
 
                //引发OnKeyDownEvent
                if (OnKeyDownEvent != null && (wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN))
                {
                    Keys keyData = (Keys)MyKBHookStruct.vkCode;
                    KeyEventArgs e = new KeyEventArgs(keyData);
                    OnKeyDownEvent(this, e);
                }
            }
            return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam);
        }

线程Hook

 private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)
        {
            if ((nCode >= 0) && (OnKeyDownEvent != null || OnKeyUpEvent != null || OnKeyPressEvent != null))
            {
               
                //引发OnKeyDownEvent
                if (OnKeyDownEvent != null && nCode==0)
                {
                    Keys keyData = (Keys)wParam;
                    KeyEventArgs e = new KeyEventArgs(keyData);
                    OnKeyDownEvent(this, e);
                }
            }
            return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam);
        }

全局/线程Hook参数结构区别

线程Hook KeyboardHookProc函数的各个参数意义如下：

nCode　　　　消息的类型，分HC_ACTION和HC_NOREMOVE

wParam　　　　按键的虚拟键码 

lParam　　　　按键的相关参数信息，包括重复时间、按键的状态（按下或弹起）等

全局Hook KeyboardHookProc函数的各个参数意义如下：

nCode　　　　消息的类型，有HC_ACTION

wParam　　　　按键的状态（按下或弹起）WM_KEYDOWN、WM_KEYUP、WM_SYSKEYDOWN、WM_SYSKEYUP

lParam　　　　指向KeyboardHookStruct结构的指针，该结构包含了按键的详细信息。

添加Hook

全局Hook

        public void Start()
        {
            if (hKeyboardHook == 0)
            {
                KeyboardHookProcedure = new HookProc(KeyboardHookProc);
                using (System.Diagnostics.Process curProcess = System.Diagnostics.Process.GetCurrentProcess())
                using (System.Diagnostics.ProcessModule curModule = curProcess.MainModule)
                    hKeyboardHook = SetWindowsHookEx(13, KeyboardHookProcedure, GetModuleHandle(curModule.ModuleName), 0);
 
                if (hKeyboardHook == 0)
                {
                    Stop();
                    throw new Exception("Set GlobalKeyboardHook failed!");
                }
            }
        }

线程Hook

   public void Start()
        {
            if (hKeyboardHook == 0)
            {
                KeyboardHookProcedure = new HookProc(KeyboardHookProc);
                hKeyboardHook = SetWindowsHookEx(2, KeyboardHookProcedure,  IntPtr.Zero, GetCurrentThreadId());
 
                if (hKeyboardHook == 0)
                {
                    Stop();
                    throw new Exception("Set GlobalKeyboardHook failed!");
                }
            }
        }

注：idHook 钩子类型，即确定钩子监听何种消息
线程钩子监听键盘消息应设为2，全局钩子监听键盘消息应设为13
线程钩子监听鼠标消息应设为7，全局钩子监听鼠标消息应设为14