C#字节和字符的转换,以及校验和计算

#region 字符串和字节数组相互转换

        /// <summary>

        /// 将字符串转换成16进制字节数组,并自动在字节数组后面加cs校验和

        /// </summary>

        /// <param name="_data">要转换的string</param>

        /// <param name="byteArray">转换之后的字节数组</param>

        /// <returns>为空则表示执行正确，否则，表示错误信息</returns>

        public static string ChangeHexStringToByteArray(string _data, out byte[] byteArray)

        {

            string sResult = "";

            byteArray = null;

            if (_data == "")

            {

                sResult = "请不要传入空值。函数：ChangeHexStringToByteArray。";

            }

            else if (_data.Length % 2 != 0)

            {

                sResult = "请传入正确的十六进制字符串，字符串的个数必须是偶数个。函数：ChangeHexStringToByteArray。";

            }

            else

            {

                try

                {

                    _data = _data.Replace(" ", "");

                    int sendLength = _data.Length / 2;

                    byteArray = new byte[sendLength];

                    string hexstring = "";

                    int k = 0;

                    for (int i = 0; i < _data.Length; )

                    {

                        hexstring = _data.Substring(i, 2);

                        int j;

                        j = int.Parse(hexstring, System.Globalization.NumberStyles.HexNumber);

                        byteArray[k] = (byte)j;

                        i += 2;

                        k++;

                    }

                }

                catch (Exception ex)

                {

                    sResult = ex.Message;

                }

            }

            return sResult;

        }

 

 

        /// <summary>

        /// 将字节数组转换成十六进制字符串

        /// </summary>

        /// <param name="data">要转换的字节数组</param>

        /// <param name="HexString">转换后的字符串</param>

        /// <returns>为空则表示执行正确，否则，表示错误信息</returns>

        public static string ChangeByteArrayToHexString(byte[] data, out string HexString)

        {

            string sResult = "";

            HexString = "";

            StringBuilder sb = new StringBuilder(data.Length * 3);

            try

            {

                foreach (byte b in data)

                    sb.Append(Convert.ToString(b, 16).PadLeft(2, '0').PadRight(3, ' '));

            }

            catch (Exception ex)

            {

                sResult = "将字节数组转换成字符串时出错，函数：ChangeByteArrayToHexString。异常信息：" + ex.Message;

            }

            HexString = sb.ToString().ToUpper();

            return sResult;

        }

 

        #endregion







  #region 计算校验和

        /// <summary>

        /// 对16进制数字的进行CRC16校验，然后把校验值返回

        /// </summary>

        /// <param name="str">要进行校验的数据</param>

        /// <param name="CRC16Result">校验值（校验结果）</param>

        /// <returns>为空则表示执行正确，否则，表示错误信息</returns>

        public string GetCRC16ResultByHexString(string str,string CRC16Result)

        {

            ushort crcResult;

            byte[] byArr;

            string sResult = "";

            CRC16Result = "";

            try

            {

                sResult = ChangeHexStringToByteArray(str, out byArr);

                if ((sResult == "") && (byArr != null))

                {

                   sResult= CalculateCRC(byArr, byArr.Length, out crcResult);

                   if (sResult == "")

                   {

                       ushort h = (byte)(crcResult & 0xFF);

                       ushort l = (byte)((crcResult & 0xFF00) >> 8);

                       string height = Convert.ToString(h, 16);

                       string low = Convert.ToString(l, 16);

                       if (height.Length == 1)

                           height = height.Insert(0, "0");

                       if (low.Length == 1)

                           low = low.Insert(0, "0");

                       CRC16Result = low.ToUpper() + height.ToUpper();

                   }

                }

            }

            catch (Exception ex)

            {

                sResult += ex.Message;

            }

 

            return sResult;

        }

 

        /// <summary>

        /// crc16算法

        /// </summary>

        /// <param name="pByte">要校验的字节数组</param>

        /// <param name="nNumberOfBytes">字节个数</param>

        /// <param name="pChecksum">校验结果</param>

        /// <returns>为空则表示执行正确，否则，表示错误信息</returns>

        public static string CalculateCRC(byte[] pByte, int nNumberOfBytes, out ushort pChecksum)

        {

            int nBit;

            ushort nShiftedBit;

            pChecksum = 0xFFFF;

            string sResult = "";

            if (nNumberOfBytes > pByte.Length)

            {

                sResult = "传入的参数nNumberOfBytes（字节个数）大于pByte（要校验的字节数组）的长度";

            }

            else

            {

                try

                {

                    for (int nByte = 0; nByte < nNumberOfBytes; nByte++)

                    {

                        pChecksum ^= pByte[nByte];

                        for (nBit = 0; nBit < 8; nBit++)

                        {

                            if ((pChecksum & 0x1) == 1)

                            {

                                nShiftedBit = 1;

                            }

                            else

                            {

                                nShiftedBit = 0;

                            }

                            pChecksum >>= 1;

                            if (nShiftedBit != 0)

                            {

                                pChecksum ^= 0xA001;

                            }

                        }

                    }

                }

                catch (Exception ex)

                {

                    sResult = ex.Message;

                }

            }

            return sResult;

        }

        /// <summary>

        /// 计算累加校验和

        /// </summary>

        /// <param name="SendByteArray">要校验的字节数组</param>

        /// <returns>对字节数组进行校验所得到的校验和</returns>

        public static byte GetSumCS(byte[] SendByteArray)

        {

            byte rst = 0x00;            

            //计算累加和

            for (int j = 2; j < SendByteArray.Length; j++)

            {

                unchecked

                {

                    rst += SendByteArray[j];

                }

            }

            //累加和计算结束

            return rst;

        }

        #endregion