C#判断文件是否被打开

[DllImport("kernel32.dll")]
        public static extern IntPtr _lopen(string lpPathName, int iReadWrite);

        [DllImport("kernel32.dll")]
        public static extern bool CloseHandle(IntPtr hObject);
        public const int OF_READWRITE = 2;
        public const int OF_SHARE_DENY_NONE = 0x40;
        public static readonly IntPtr HFILE_ERROR = new IntPtr(-1);

        /// <summary>
        /// 文件是否被打开
        /// </summary>
        /// <param name="path"></param>
        /// <returns></returns>
        public static bool IsFileOpen(string path)
        {
            if (!File.Exists(path))
            {
                return false;
            }
            IntPtr vHandle = _lopen(path, OF_READWRITE | OF_SHARE_DENY_NONE);//windows Api上面有定义扩展方法
            if (vHandle == HFILE_ERROR)
            {
                return true;
            }
            CloseHandle(vHandle);
            return false;
        }