hook keyboard : how to get the name of program where the key is pressed?

Question

I made a simple hook keyboard in C#, so i have this following code :

        private static IntPtr hKeyboardHook = IntPtr.Zero;
        private const int WH_KEYBOARD_LL = 13;
        private const int WM_KEYDOWN = 0x100;

        private delegate IntPtr LowLevelKeyboardProc(int nCode, IntPtr wParam, IntPtr lParam);
        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        private static extern IntPtr SetWindowsHookEx(int idHook, LowLevelKeyboardProc lpfn, IntPtr hMod, uint dwThreadId);
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall, SetLastError = true)]
        private static extern int UnhookWindowsHookEx(IntPtr idHook);
        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);
        [DllImport("user32")]
        private static extern int ToAscii(int uVirtKey, int uScanCode, byte[] lpbKeyState, byte[] lpwTransKey, int fuState);
        [DllImport("user32")]
        private static extern int GetKeyboardState(byte[] pbKeyState);
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
        private static extern short GetKeyState(int vKey);
        private delegate int HookProc(int nCode, int wParam, IntPtr lParam);
        [DllImport("kernel32.dll")]
        public static extern IntPtr GetModuleHandle(string lpModuleName);
        private static LowLevelKeyboardProc _proc = HookCallback;

 public void initialization()
        {
            using (Process curProcess = Process.GetCurrentProcess())
                using (ProcessModule curModule = curProcess.MainModule)
                {
                    hKeyboardHook = SetWindowsHookEx(WH_KEYBOARD_LL, _proc, GetModuleHandle(curModule.ModuleName), 0);
                }  
        }

    private static IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)
    {
        if (nCode >= 0 && wParam == (IntPtr)WM_KEYDOWN)
        {
            int vkCode = Marshal.ReadInt32(lParam);
            if (vkCode >= 32 && vkCode < 160)
                Console.Write((Keys)vkCode);
            if (vkCode == 13)
                Console.WriteLine("\n");
        }
        return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam);
    }

It works fine with no problem !! my program grip all key pressed in other program and write it on the console. But i want to have the name of the program where the key is pressed, and i don't know how i can do that.

Anyone can help me ?

Answer 1

You are using a low-level hook ( WH_KEYBOARD_LL ). Low-level hooks are dispatched before the window manager decides which program will receive the message. Therefore, there is no "name of the program where the key is pressed" because the window manager hasn't yet decided which program the keypress will be delivered to. (You can try to guess by calling GetForegroundWindow .)

(Just curious: What is the ultimate problem you're trying to solve by using a keyboard hook? Maybe there's a better way. I hope you're not writing a keylogger.)