关于 HOOK 捕获键盘 的操作出现的问题

Question

public class Hook3
    {        public delegate void HookProc(int nCode, int wParam, IntPtr lParam);        HookProc KeyHandle;        static int hHook = 0;        public const int WH_KEYBOARD_LL = 13;        #region DllImport        //设置钩子  
        [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)]
        //抽掉钩子 
        public static extern bool UnhookWindowsHookEx(int idHook);
        [DllImport("user32.dll")]
        //调用下一个钩子  
        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);        [StructLayout(LayoutKind.Sequential)]
        public class KeyBoardHookStruct
        {
            public int vkCode;
            public int scanCode;
            public int flags;
            public int time;
            public int dwExtraInfo;
        }        #endregion        public Hook3()
        { 
            
        }        //开始
        public void Start()
        {
            KeyHandle += new HookProc(this.HookProcMethod);
            hHook = SetWindowsHookEx(WH_KEYBOARD_LL, KeyHandle, GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), 0);
        }        //开始处理 记录
        private void HookProcMethod(int nCode, int wParam, IntPtr lParam)
        {
            KeyBoardHookStruct KBHS = (KeyBoardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyBoardHookStruct));
            System.Console.Write(KBHS.vkCode.ToString());
            //return KBHS.vkCode;
        }        //析构函数
        ~Hook3()
        {
            UnhookWindowsHookEx(hHook);
        }
    }
上面是代码 为什么每次捕获的我键盘事件 都会出现问题 
我按了一下键盘 可他捕获却是输出的2次 等待高手帮忙解决