c# 判断一个文件是否正在被使用

        public static bool IsInUse(string fileName)        {            bool inUse = true;            if (File.Exists(fileName))            {                FileStream fs = null;                try                {                    fs = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.None);                    inUse = false;                }                catch (Exception e)                {                    Console.WriteLine(e.Message.ToString());                }                finally                {                    if (fs != null)                    {                        fs.Close();                    }                }                return inUse;             }            else            {                return false;             }        }