关键代码：

        /// <summary>        /// 获取文件大小—字节        /// </summary>        /// <param name="filePath">文件路径</param>        /// <returns>文件大小</returns>        public static long GetSize(string filePath)        {            long _size = 0;            try            {                if (File.Exists(filePath))                {                    FileStream _stream = new FileStream(filePath, FileMode.Open);                    _size = _stream.Length;                    _stream.Close();                    _stream.Dispose();                }            }            catch (Exception ex)            {                _size = 0;                Debug.WriteLine(string.Format("获取文件大小异常，原因：{0}", ex.Message));            }            return _size;        }        /// <summary>        /// 获取文件大小—kb        /// </summary>        /// <param name="filePath">文件路径</param>        /// <returns>文件大小_kb</returns>        public static double GetKBSize(string filePath)        {            double _kb = 0;            long _size = GetSize(filePath);            if (_size != 0)            {                _kb = _size / 1024d;            }            return _kb;        }        /// <summary>        /// 获取文件大小—mb        /// </summary>        /// <param name="filePath">文件路径</param>        /// <returns>文件大小_mb</returns>        public static double GetMBSize(string filePath)        {            double _mb = 0;            long _size = GetSize(filePath);            if (_size != 0)            {                _mb = _size / 1048576d;//1024*1024==1048576;            }            return _mb;        }代码比较简单，那么我们来测试一下，有一个一兆多日志文件，来读取下，如图：

测试代码：

                string _path = @"C:\CodePlex\CSharpUtilHelp\UtilHelp\LogUtilHelpV2Test\bin\Release\Log\20140731.log";                Console.WriteLine("File Size:" + FileToolV2.GetSize(_path));                Console.WriteLine("File Size_kb:" + FileToolV2.GetKBSize(_path) + " kb");                Console.WriteLine("File Size_mb:" + FileToolV2.GetMBSize(_path) + " mb");

测试效果：

希望有所帮助！

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