哪位朋友能帮个忙，把我的这段VC代码改成C#代码！！！

Question

我这个可以用
using System;
using System.Collections.Generic;
using System.Text;
using System.IO;namespace CRC
{
    /// <summary>
    /// CRC32校验
    /// </summary>
    public sealed class CRC32
    {
        static CRC32()
        {
            GetCRC32Table();
        }        private static ulong[] Crc32Table;
        
        /// <summary>
        /// 生成CRC32码表
        /// </summary>
        private static void GetCRC32Table() 
        {
            ulong Crc;
            Crc32Table = new ulong[256];
            int i,j;
            for(i = 0;i < 256; i++) 
            {
                Crc = (ulong)i;
                for (j = 8; j > 0; j--)
                {
                    if ((Crc & 1) == 1)
                        Crc = (Crc >> 1) ^ 0xEDB88320;
                    else
                        Crc >>= 1;
                }
                Crc32Table[i] = Crc;
            }
        }        /// <summary>
        /// 字节数组校验
        /// </summary>
        /// <param name="buffer">ref 字节数组</param>
        /// <returns></returns>
        public static ulong ByteCRC(ref byte[] buffer)
        {
            ulong value = 0xffffffff;
            ulong len = (ulong)buffer.Length;
            for (ulong i = 0; i < len; i++)
            {
                value = (value >> 8) ^ Crc32Table[(value & 0xFF) ^ buffer[i]];
            }
            return value ^ 0xffffffff;
        }        /// <summary>
        /// 字符串校验
        /// </summary>
        /// <param name="sInputValue">字符串</param>
        /// <returns></returns>
        public static ulong StringCRC(string sInputValue)
        {
            byte[] buffer = Encoding.ASCII.GetBytes(sInputValue);
            return ByteCRC(ref buffer);
        }        /// <summary>
        /// 文件校验
        /// </summary>
        /// <param name="sInputFilename">文件名</param>
        /// <returns></returns>
        public static ulong FileCRC(string sInputFileName)
        {
            FileStream inFile = new System.IO.FileStream(sInputFileName, System.IO.FileMode.Open, System.IO.FileAccess.Read);
            byte[] bInput = new byte[inFile.Length];
            inFile.Read(bInput, 0, bInput.Length);
            inFile.Close();            return ByteCRC(ref bInput);
        }
    }
}