通用方法-获取文件的大小（字节）-字节转为MB｜KB

  /// <summary>
        /// 获取文件的大小（字节）
        /// </summary>
        /// <param name="fullPath"></param>
        /// <returns></returns>
        public static long get_file_size_by_full_path(string fullPath)
        {
            try
            {
                return new FileInfo(fullPath).Length;
            }
            catch
            {
                return 0;
            }
        }

        /// <summary>
        /// 字节转为MB｜KB
        /// </summary>
        /// <param name="v"></param>
        /// <returns></returns>
        public static string to_kb_mb_GB_from_bytes(this long v)
        {
            if (v > 1048576) return Math.Round(v.ToString().ToDouble() / 1024 / 1024, 2) + " MB";

            return Math.Round(v.ToString().ToDouble() / 1024, 2) + " KB";
        }

　　

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