NativeMethod.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;

namespace RecordMenuHook {

    class NativeMethod {

        public delegate IntPtr HookProc(int code, IntPtr wParam, IntPtr lParam);

        [DllImport("user32.dll", SetLastError = true)]
        public static extern IntPtr SetWindowsHookEx(NativeEnum.HookType hookType, HookProc lpfn, IntPtr hMod, uint dwThreadId);

        [DllImport("user32.dll", SetLastError = true)]
        public static extern bool UnhookWindowsHookEx(IntPtr hhk);

        [DllImport("user32.dll")]
        public static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);

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

        [DllImport("user32.dll")]
        public static extern int SendMessage(IntPtr hwnd, uint wMsg, IntPtr wParam, IntPtr lParam);

        [StructLayout(LayoutKind.Sequential)]
        public struct MSG {
            public IntPtr hwnd;
            public uint message;
            public UIntPtr wParam;
            public IntPtr lParam;
            public int time;
            public POINT pt;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct POINT {
            public int X;
            public int Y;

            public POINT(int x, int y) {
                this.X = x;
                this.Y = y;
            }

            public static implicit operator System.Drawing.Point(POINT p) {
                return new System.Drawing.Point(p.X, p.Y);
            }

            public static implicit operator POINT(System.Drawing.Point p) {
                return new POINT(p.X, p.Y);
            }
        }

        [StructLayout(LayoutKind.Sequential)]
        public class KBDLLHOOKSTRUCT {
            public uint vkCode;
            public uint scanCode;
            public NativeEnum.KBDLLHOOKSTRUCTFlags flags;
            public uint time;
            public UIntPtr dwExtraInfo;
        }
    }
}