private static HookResult HookGlobal(int hookId, Callback callback)
        {
            _globalHookProc = (code, param, lParam) => HookProcedure(code, param, lParam, callback);

            var hookHandle = HookNativeMethods.SetWindowsHookEx(
                hookId,
                _globalHookProc,
                Process.GetCurrentProcess().MainModule.BaseAddress,
                0);

            if (hookHandle.IsInvalid)
            {
                ThrowLastUnmanagedErrorAsException();
            }

            return(new HookResult(hookHandle, _globalHookProc));
        }
        private static HookResult HookApp(int hookId, Callback callback)
        {
            _appHookProc = (code, param, lParam) => HookProcedure(code, param, lParam, callback);

            var hookHandle = HookNativeMethods.SetWindowsHookEx(
                hookId,
                _appHookProc,
                IntPtr.Zero,
                ThreadNativeMethods.GetCurrentThreadId());

            if (hookHandle.IsInvalid)
            {
                ThrowLastUnmanagedErrorAsException();
            }

            return(new HookResult(hookHandle, _appHookProc));
        }