DotNet指定文件显示的尺寸

 [System.ComponentModel.EditorBrowsable(System.ComponentModel.EditorBrowsableState.Never)]
    public static class FsLibValueExtract
    {
        readonly static string[] SizeDefinitions = { "字节", "KB", "MB", "GB", "TB" };

        /// <summary>
        /// 控制尺寸显示转换上限
        /// </summary>
        readonly static double SizeLevel = 0x400 * 0.9;

        /// <summary>
        /// 转换为尺寸显示方式
        /// </summary>
        /// <param name="size">大小</param>
        /// <returns>尺寸显示方式</returns>
        public static string ToSizeDescription(this double size)
        {
            return ToSizeDescription(size, 2);
        }

        /// <summary>
        /// 转换为尺寸显示方式
        /// </summary>
        /// <param name="size">大小</param>
        /// <param name="digits">小数位数</param>
        /// <returns>尺寸显示方式</returns>
        public static string ToSizeDescription(this double size, int digits)
        {
            var sizeDefine = 0;

            while (sizeDefine < SizeDefinitions.Length && size > SizeLevel)
            {
                size /= 0x400;
                sizeDefine++;
            }

            if (sizeDefine == 0) return size.ToString("#0") + " " + SizeDefinitions[sizeDefine];
            return size.ToString("#0." + string.Empty.PadLeft(digits, '#')) + " " + SizeDefinitions[sizeDefine];
        }

        /// <summary>
        /// 转换为尺寸显示方式
        /// </summary>
        /// <param name="size">大小</param>
        /// <returns>尺寸显示方式</returns>
        public static string ToSizeDescription(this ulong size)
        {
            return ((double)size).ToSizeDescription();
        }

        /// <summary>
        /// 转换为尺寸显示方式
        /// </summary>
        /// <param name="size">大小</param>
        /// <param name="digits">小数位数</param>
        /// <returns>尺寸显示方式</returns>
        public static string ToSizeDescription(this ulong size, int digits)
        {
            return ((double)size).ToSizeDescription(digits);
        }

        /// <summary>
        /// 转换为尺寸显示方式
        /// </summary>
        /// <param name="size">大小</param>
        /// <returns>尺寸显示方式</returns>
        public static string ToSizeDescription(this long size)
        {
            return ((double)size).ToSizeDescription();
        }

        /// <summary>
        /// 转换为尺寸显示方式
        /// </summary>
        /// <param name="size">大小</param>
        /// <param name="digits">小数位数</param>
        /// <returns>尺寸显示方式</returns>
        public static string ToSizeDescription(this long size, int digits)
        {
            return ((double)size).ToSizeDescription(digits);
        }

        /// <summary>
        /// 转换为尺寸显示方式
        /// </summary>
        /// <param name="size">大小</param>
        /// <returns>尺寸显示方式</returns>
        public static string ToSizeDescription(this int size)
        {
            return ((double)size).ToSizeDescription();
        }

        /// <summary>
        /// 转换为尺寸显示方式
        /// </summary>
        /// <param name="size">大小</param>
        /// <param name="digits">小数位数</param>
        /// <returns>尺寸显示方式</returns>
        public static string ToSizeDescription(this int size, int digits)
        {
            return ((double)size).ToSizeDescription(digits);
        }
    }