1 /// <summary> 2 /// 报文解析转换类 3 /// </summary> 4 public class DatagramConvert 5 { 6 public static Encoding ENCODING_ASCII = Encoding.ASCII; 7 public static Encoding ENCODING_GB2312 = Encoding.GetEncoding("gb2312"); 8 public static Crc16Ccitt CRC16 = new Crc16Ccitt(InitialCrcValue.NonZero1); 9 10 #region 数据转换、解析相关方法 11 /// <summary> 12 /// 解析报文信息,返回完整的报文内容列表 13 /// </summary> 14 /// <param name="datagram"></param> 15 /// <param name="startTag"></param> 16 /// <returns></returns> 17 public static List<string> DatagramParser(ref string datagram, string startTag = "FAF5") 18 { 19 List<string> list = new List<string>(); 20 if (string.IsNullOrWhiteSpace(datagram)) 21 { 22 return list; 23 } 24 int index; 25 while ((index = datagram.IndexOf(startTag)) > -1) 26 { 27 if (datagram.Length <= index + 6) // 判断是否包含长度信息 28 { 29 break; 30 } 31 int len = Convert.ToInt32(datagram.Substring(index + 4, 2), 16) * 2; // 获取数据包长度 32 if (datagram.Length < index + len + 10) // 判断是否包含完整的报文 33 { 34 break; 35 } 36 string newDatagram = datagram.Substring(index, len + 10); // 获取完整的报文 37 list.Add(newDatagram); 38 datagram = datagram.Substring(index + len + 10); // 获取余下的报文信息 39 } 40 41 return list; 42 } 43 44 /// <summary> 45 /// 拆分数据 46 /// </summary> 47 /// <param name="msgs">2位长度的hex字符串数组</param> 48 /// <param name="start">开始索引</param> 49 /// <param name="end">截止位置</param> 50 /// <param name="msgtype"></param> 51 /// <returns></returns> 52 public static object GetString(string[] msgs, int start, int end, string msgtype) 53 { 54 List<byte> msgarry = new List<byte>(); 55 string msg = "0x"; 56 for (int i = start; i <= end; i++) 57 { 58 if (msgtype == "string") 59 { 60 msgarry.Add((byte)Convert.ToInt32(msgs[i], 16)); 61 } 62 else 63 { 64 msg += msgs[i]; 65 } 66 } 67 if (msgtype == "string") 68 { 69 return msgarry; 70 } 71 else 72 { 73 return msg; 74 } 75 } 76 77 /// <summary> 78 /// 向集合中添加批量添加元素 79 /// </summary> 80 /// <param name="bitarry"></param> 81 /// <param name="list"></param> 82 public static void AddRange(string[] bitarry, ref List<string> list) 83 { 84 for (int i = 0; i < bitarry.Length; i++) 85 { 86 list.Add(bitarry[i]); 87 } 88 } 89 90 /// <summary> 91 /// 从字节数组中提取固定长度的元素,提取个数超出数组大小时填充(byte)0 92 /// </summary> 93 /// <param name="bts">字节数组</param> 94 /// <param name="count">提取长度</param> 95 /// <returns></returns> 96 public static byte[] BytesExtract(byte[] bts, int count) 97 { 98 byte[] returnBytes = new byte[count]; 99 for (int i = 0; i < bts.Length && i < count; i++) 100 { 101 returnBytes[i] = bts[i]; 102 } 103 if (bts.Length < count) 104 { 105 for (int i = bts.Length; i < count; i++) 106 { 107 returnBytes[i] = Convert.ToByte(0); 108 } 109 } 110 return returnBytes; 111 } 112 113 /// <summary> 114 /// 将字节数组转换为制定长度的16位字符串数组 115 /// </summary> 116 /// <param name="bts">字节数组</param> 117 /// <param name="count">返回字符串长度</param> 118 /// <returns></returns> 119 public static string[] BytesToHexArray(byte[] bts, int count) 120 { 121 string[] returnBytes = new string[count]; 122 for (int i = 0; i < bts.Length; i++) 123 { 124 returnBytes[i] = Convert10To16(bts[i]).ToUpper(); 125 } 126 if (bts.Length < count) 127 { 128 for (int i = bts.Length; i < count; i++) 129 { 130 returnBytes[i] = "00"; 131 } 132 } 133 return returnBytes; 134 } 135 136 /// <summary> 137 /// 16进制字符串按2个长度分割成字节数组 138 /// </summary> 139 /// <param name="hexString"></param> 140 /// <returns></returns> 141 public static byte[] HexStringToBytes(string hexString) 142 { 143 hexString = hexString.Replace(" ", ""); 144 if ((hexString.Length % 2) != 0) 145 hexString += " "; 146 byte[] returnBytes = new byte[hexString.Length / 2]; 147 for (int i = 0; i < returnBytes.Length; i++) 148 returnBytes[i] = Convert.ToByte(hexString.Substring(i * 2, 2), 16); 149 return returnBytes; 150 } 151 152 /// <summary> 153 /// 将16进制字符串按2个长度进行分割 154 /// </summary> 155 /// <param name="hexString">16进制字符串</param> 156 /// <returns></returns> 157 public static string[] HexStringToArray(string hexString) 158 { 159 hexString = hexString.Replace(" ", ""); 160 if ((hexString.Length % 2) != 0) 161 hexString += " "; 162 string[] returnBytes = new string[hexString.Length / 2]; 163 for (int i = 0; i < returnBytes.Length; i++) 164 returnBytes[i] = hexString.Substring(i * 2, 2); 165 return returnBytes; 166 } 167 168 /// <summary> 169 /// 十进制转十六进制 170 /// </summary> 171 /// <param name="value"></param> 172 /// <returns></returns> 173 public static string Convert10To16(int value) 174 { 175 return Convert.ToString(value, 16); 176 } 177 178 /// <summary> 179 /// 十进制转十六进制 180 /// </summary> 181 /// <param name="value"></param> 182 /// <returns></returns> 183 public static string Convert10To16(long value) 184 { 185 return Convert.ToString(value, 16); 186 } 187 188 /// <summary> 189 /// 十进制转十六进制 190 /// </summary> 191 /// <param name="value"></param> 192 /// <returns></returns> 193 public static int Convert10To16(string value) 194 { 195 return Convert.ToInt32(value, 16); 196 } 197 198 /// <summary> 199 /// 十进制转十六进制 200 /// </summary> 201 /// <param name="value"></param> 202 /// <returns></returns> 203 public static int Convert16To10(string value) 204 { 205 return Convert.ToInt32(value, 16); 206 } 207 208 /// <summary> 209 /// 数据类型转换示例 210 /// </summary> 211 private static void DataConvertDemo() 212 { 213 //十进制转二进制 214 215 Console.WriteLine(Convert.ToString(69, 2)); 216 217 //十进制转八进制 218 219 Console.WriteLine(Convert.ToString(69, 8)); 220 221 //十进制转十六进制 222 223 Console.WriteLine(Convert.ToString(69, 16)); 224 225 //二进制转十进制 226 227 Console.WriteLine(Convert.ToInt32("100111101", 2)); 228 229 //八进制转十进制 230 231 Console.WriteLine(Convert.ToInt32("76", 8)); 232 233 //C# 16进制转换10进制 234 235 Console.WriteLine(Convert.ToInt32("FF", 16)); 236 237 } 238 239 /// <summary> 240 /// CRC异或校验 241 /// </summary> 242 /// <param name="cmdString">命令字符串</param> 243 /// <returns></returns> 244 public static string CRC(string cmdString) 245 { 246 try 247 { 248 //CRC寄存器 249 int CRCCode = 0; 250 // 将字符串拆分成为16进制字节数据然后两位两位进行异或校验 251 for (int i = 1; i < cmdString.Length / 2; i++) 252 { 253 string cmdHex = cmdString.Substring(i * 2, 2); 254 if (i == 1) 255 { 256 string cmdPrvHex = cmdString.Substring((i - 1) * 2, 2); 257 CRCCode = (byte)Convert.ToInt32(cmdPrvHex, 16) ^ (byte)Convert.ToInt32(cmdHex, 16); 258 } 259 else 260 { 261 CRCCode = (byte)CRCCode ^ (byte)Convert.ToInt32(cmdHex, 16); 262 } 263 } 264 return CRCCode.ToString("X2");// 返回16进制校验码 265 } 266 catch 267 { 268 return "00"; 269 } 270 } 271 #endregion 272 }
CRC-16-CCITT效验类
1 /// <summary> 2 /// 循环冗余检验:CRC-16-CCITT查表法 3 /// </summary> 4 public static class CRCITU16 5 { 6 /// <summary> 7 /// 计算给定长度数据的16位CRC 8 /// </summary> 9 /// <param name="data">要计算CRC的字节数组</param> 10 /// <returns>CRC值</returns> 11 public static UInt16 GetCrc16(Byte[] data) 12 { // 初始化 13 Int32 High = 0xFF; // 高字节 14 Int32 Low = 0xFF; // 低字节 15 if (data != null) 16 { 17 foreach (Byte b in data) 18 { 19 Int32 Index = Low ^ b; 20 Low = High ^ CRC16TABLE_LO[Index]; 21 High = CRC16TABLE_HI[Index]; 22 } 23 } 24 25 return (UInt16)(~((High << 8) + Low)); // 取反 26 } 27 28 /// <summary> 29 /// 检查给定长度数据的16位CRC是否正确 30 /// </summary> 31 /// <param name="data">要校验的字节数组</param> 32 /// <returns> 33 /// true:正确 34 /// false:错误 35 /// </returns> 36 /// <reamrks> 37 /// 字节数组最后2个字节为校验码,且低字节在前面,高字节在后面 38 /// </reamrks> 39 public static Boolean IsCrc16Good(Byte[] data) 40 { 41 // 初始化 42 Int32 High = 0xFF; 43 Int32 Low = 0xFF; 44 if (data != null) 45 { 46 foreach (Byte b in data) 47 { 48 Int32 Index = Low ^ b; 49 Low = High ^ CRC16TABLE_LO[Index]; 50 High = CRC16TABLE_HI[Index]; 51 } 52 } 53 54 return (High == 0xF0 && Low == 0xB8); 55 } 56 57 /// <summary> 58 /// CRC16查找表高字节 59 /// </summary> 60 private static readonly Byte[] CRC16TABLE_HI = 61 { 62 0x00, 0x11, 0x23, 0x32, 0x46, 0x57, 0x65, 0x74, 0x8C, 0x9D, 0xAF, 0xBE, 0xCA, 0xDB, 0xE9, 0xF8, 63 0x10, 0x01, 0x33, 0x22, 0x56, 0x47, 0x75, 0x64, 0x9C, 0x8D, 0xBF, 0xAE, 0xDA, 0xCB, 0xF9, 0xE8, 64 0x21, 0x30, 0x02, 0x13, 0x67, 0x76, 0x44, 0x55, 0xAD, 0xBC, 0x8E, 0x9F, 0xEB, 0xFA, 0xC8, 0xD9, 65 0x31, 0x20, 0x12, 0x03, 0x77, 0x66, 0x54, 0x45, 0xBD, 0xAC, 0x9E, 0x8F, 0xFB, 0xEA, 0xD8, 0xC9, 66 0x42, 0x53, 0x61, 0x70, 0x04, 0x15, 0x27, 0x36, 0xCE, 0xDF, 0xED, 0xFC, 0x88, 0x99, 0xAB, 0xBA, 67 0x52, 0x43, 0x71, 0x60, 0x14, 0x05, 0x37, 0x26, 0xDE, 0xCF, 0xFD, 0xEC, 0x98, 0x89, 0xBB, 0xAA, 68 0x63, 0x72, 0x40, 0x51, 0x25, 0x34, 0x06, 0x17, 0xEF, 0xFE, 0xCC, 0xDD, 0xA9, 0xB8, 0x8A, 0x9B, 69 0x73, 0x62, 0x50, 0x41, 0x35, 0x24, 0x16, 0x07, 0xFF, 0xEE, 0xDC, 0xCD, 0xB9, 0xA8, 0x9A, 0x8B, 70 0x84, 0x95, 0xA7, 0xB6, 0xC2, 0xD3, 0xE1, 0xF0, 0x08, 0x19, 0x2B, 0x3A, 0x4E, 0x5F, 0x6D, 0x7C, 71 0x94, 0x85, 0xB7, 0xA6, 0xD2, 0xC3, 0xF1, 0xE0, 0x18, 0x09, 0x3B, 0x2A, 0x5E, 0x4F, 0x7D, 0x6C, 72 0xA5, 0xB4, 0x86, 0x97, 0xE3, 0xF2, 0xC0, 0xD1, 0x29, 0x38, 0x0A, 0x1B, 0x6F, 0x7E, 0x4C, 0x5D, 73 0xB5, 0xA4, 0x96, 0x87, 0xF3, 0xE2, 0xD0, 0xC1, 0x39, 0x28, 0x1A, 0x0B, 0x7F, 0x6E, 0x5C, 0x4D, 74 0xC6, 0xD7, 0xE5, 0xF4, 0x80, 0x91, 0xA3, 0xB2, 0x4A, 0x5B, 0x69, 0x78, 0x0C, 0x1D, 0x2F, 0x3E, 75 0xD6, 0xC7, 0xF5, 0xE4, 0x90, 0x81, 0xB3, 0xA2, 0x5A, 0x4B, 0x79, 0x68, 0x1C, 0x0D, 0x3F, 0x2E, 76 0xE7, 0xF6, 0xC4, 0xD5, 0xA1, 0xB0, 0x82, 0x93, 0x6B, 0x7A, 0x48, 0x59, 0x2D, 0x3C, 0x0E, 0x1F, 77 0xF7, 0xE6, 0xD4, 0xC5, 0xB1, 0xA0, 0x92, 0x83, 0x7B, 0x6A, 0x58, 0x49, 0x3D, 0x2C, 0x1E, 0x0F 78 }; 79 80 /// <summary> 81 /// CRC16查找表低字节 82 /// </summary> 83 private static readonly Byte[] CRC16TABLE_LO = 84 { 85 0x00, 0x89, 0x12, 0x9B, 0x24, 0xAD, 0x36, 0xBF, 0x48, 0xC1, 0x5A, 0xD3, 0x6C, 0xE5, 0x7E, 0xF7, 86 0x81, 0x08, 0x93, 0x1A, 0xA5, 0x2C, 0xB7, 0x3E, 0xC9, 0x40, 0xDB, 0x52, 0xED, 0x64, 0xFF, 0x76, 87 0x02, 0x8B, 0x10, 0x99, 0x26, 0xAF, 0x34, 0xBD, 0x4A, 0xC3, 0x58, 0xD1, 0x6E, 0xE7, 0x7C, 0xF5, 88 0x83, 0x0A, 0x91, 0x18, 0xA7, 0x2E, 0xB5, 0x3C, 0xCB, 0x42, 0xD9, 0x50, 0xEF, 0x66, 0xFD, 0x74, 89 0x04, 0x8D, 0x16, 0x9F, 0x20, 0xA9, 0x32, 0xBB, 0x4C, 0xC5, 0x5E, 0xD7, 0x68, 0xE1, 0x7A, 0xF3, 90 0x85, 0x0C, 0x97, 0x1E, 0xA1, 0x28, 0xB3, 0x3A, 0xCD, 0x44, 0xDF, 0x56, 0xE9, 0x60, 0xFB, 0x72, 91 0x06, 0x8F, 0x14, 0x9D, 0x22, 0xAB, 0x30, 0xB9, 0x4E, 0xC7, 0x5C, 0xD5, 0x6A, 0xE3, 0x78, 0xF1, 92 0x87, 0x0E, 0x95, 0x1C, 0xA3, 0x2A, 0xB1, 0x38, 0xCF, 0x46, 0xDD, 0x54, 0xEB, 0x62, 0xF9, 0x70, 93 0x08, 0x81, 0x1A, 0x93, 0x2C, 0xA5, 0x3E, 0xB7, 0x40, 0xC9, 0x52, 0xDB, 0x64, 0xED, 0x76, 0xFF, 94 0x89, 0x00, 0x9B, 0x12, 0xAD, 0x24, 0xBF, 0x36, 0xC1, 0x48, 0xD3, 0x5A, 0xE5, 0x6C, 0xF7, 0x7E, 95 0x0A, 0x83, 0x18, 0x91, 0x2E, 0xA7, 0x3C, 0xB5, 0x42, 0xCB, 0x50, 0xD9, 0x66, 0xEF, 0x74, 0xFD, 96 0x8B, 0x02, 0x99, 0x10, 0xAF, 0x26, 0xBD, 0x34, 0xC3, 0x4A, 0xD1, 0x58, 0xE7, 0x6E, 0xF5, 0x7C, 97 0x0C, 0x85, 0x1E, 0x97, 0x28, 0xA1, 0x3A, 0xB3, 0x44, 0xCD, 0x56, 0xDF, 0x60, 0xE9, 0x72, 0xFB, 98 0x8D, 0x04, 0x9F, 0x16, 0xA9, 0x20, 0xBB, 0x32, 0xC5, 0x4C, 0xD7, 0x5E, 0xE1, 0x68, 0xF3, 0x7A, 99 0x0E, 0x87, 0x1C, 0x95, 0x2A, 0xA3, 0x38, 0xB1, 0x46, 0xCF, 0x54, 0xDD, 0x62, 0xEB, 0x70, 0xF9, 100 0x8F, 0x06, 0x9D, 0x14, 0xAB, 0x22, 0xB9, 0x30, 0xC7, 0x4E, 0xD5, 0x5C, 0xE3, 0x6A, 0xF1, 0x78 101 }; 102 }
CRC-32-IEEE效验类
1 /// <summary> 2 /// 循环冗余检验:CRC-32-IEEE 802.3查表法 3 /// </summary> 4 public static class CRCITU32 5 { 6 /// <summary> 7 /// 计算给定长度数据的32位CRC 8 /// </summary> 9 /// <param name="data">要计算CRC的字节数组</param> 10 /// <returns>CRC值</returns> 11 public static UInt32 GetCrc32(Byte[] data) 12 { 13 UInt32 crcValue = 0xFFFFFFFF; 14 if (data != null) 15 { 16 foreach (Byte b in data) 17 { 18 crcValue = (crcValue >> 8) ^ CRC32TABLE[(crcValue ^ b) & 0xFF]; 19 } 20 } 21 22 return ~crcValue; 23 } 24 25 private static readonly UInt32[] CRC32TABLE = 26 { 27 0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3, 28 0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91, 29 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, 30 0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5, 31 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 32 0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59, 33 0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F, 34 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, 35 0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433, 36 0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01, 37 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 38 0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65, 39 0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB, 40 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, 41 0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F, 42 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD, 43 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683, 44 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1, 45 0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7, 46 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, 47 0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B, 48 0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79, 49 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, 50 0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D, 51 0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713, 52 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, 53 0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777, 54 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45, 55 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, 56 0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9, 57 0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF, 58 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D 59 }; 60 }
Crc16Ccitt效验类
1 /// <summary> 2 /// 初始效验值 3 /// </summary> 4 public enum InitialCrcValue { Zeros, NonZero1 = 0xffff, NonZero2 = 0x1D0F } 5 6 /// <summary> 7 /// Crc16Ccitt效验类 8 /// </summary> 9 public class Crc16Ccitt 10 { 11 const ushort poly = 4129; 12 ushort[] table = new ushort[256]; 13 ushort initialValue = 0; 14 15 public ushort ComputeChecksum(byte[] bytes) 16 { 17 ushort crc = this.initialValue; 18 for (int i = 0; i < bytes.Length; ++i) 19 { 20 crc = (ushort)((crc << 8) ^ table[((crc >> 8) ^ (0xff & bytes[i]))]); 21 } 22 return crc; 23 } 24 25 public byte[] ComputeChecksumBytes(byte[] bytes) 26 { 27 ushort crc = ComputeChecksum(bytes); 28 return BitConverter.GetBytes(crc); 29 } 30 31 public Crc16Ccitt(InitialCrcValue initialValue) 32 { 33 this.initialValue = (ushort)initialValue; 34 ushort temp, a; 35 for (int i = 0; i < table.Length; ++i) 36 { 37 temp = 0; 38 a = (ushort)(i << 8); 39 for (int j = 0; j < 8; ++j) 40 { 41 if (((temp ^ a) & 0x8000) != 0) 42 { 43 temp = (ushort)((temp << 1) ^ poly); 44 } 45 else 46 { 47 temp <<= 1; 48 } 49 a <<= 1; 50 } 51 table[i] = temp; 52 } 53 } 54 }