常用编码工具类,支持base64,md5,des,crc32

using  System; using  System.IO; using  System.Security; using  System.Security.Cryptography; using  System.Runtime.InteropServices; using  System.Text; namespace  YNEC.Services.Encrypt  ... {  /**//**//**//// <summary>  /// CRC 效验  /// 快速检测算法  /// </summary>  public class CRC32...{    protected ulong[] crc32Table;    /**//**//**//// <summary>    /// 构造：初始化效验表    /// </summary>    public CRC32() ...{      const ulong ulPolynomial = 0xEDB88320;      ulong dwCrc;      crc32Table = new ulong[256];      int i,j;      for(i = 0; i < 256; i++) ...{        dwCrc = (ulong)i;        for(j = 8; j > 0; j--) ...{          if((dwCrc & 1)==1)            dwCrc = (dwCrc >> 1) ^ ulPolynomial;          else            dwCrc >>= 1;        }        crc32Table[i] = dwCrc;      }    }    /**//**//**//// <summary>    /// 字节数组效验    /// </summary>    /// <param name="buffer">ref 字节数组</param>    /// <returns></returns>    public ulong ByteCRC(ref byte[] buffer) ...{      ulong ulCRC = 0xffffffff;       ulong len;       len = (ulong)buffer.Length;      for (ulong buffptr=0; buffptr < len; buffptr++) ...{             ulong tabPtr = ulCRC & 0xFF;        tabPtr = tabPtr ^ buffer[buffptr];        ulCRC = ulCRC >> 8;        ulCRC = ulCRC ^ crc32Table[tabPtr];      }      return ulCRC ^ 0xffffffff;     }    /**//**//**//// <summary>    /// 字符串效验    /// </summary>    /// <param name="sInputString">字符串</param>    /// <returns></returns>    public ulong StringCRC(string sInputString)...{      byte[] buffer = Encoding.Default.GetBytes(sInputString);      return ByteCRC(ref buffer);    }    /**//**//**//// <summary>    /// 文件效验    /// </summary>    /// <param name="sInputFilename">输入文件</param>    /// <returns></returns>    public 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);    }  }  /**//**//**//// <summary>  /// MD5 无逆向编码  /// 获取唯一特征串，可用于密码加密  /// (无法还原)  /// </summary>  public class MD5 ...{    public MD5()...{    }    /**//**//**//// <summary>    /// 获取字符串的特征串    /// </summary>    /// <param name="sInputString">输入文本</param>    /// <returns></returns>    public string HashString(string sInputString)...{      System.Security.Cryptography.MD5 md5 = System.Security.Cryptography.MD5.Create();      string encoded = BitConverter.ToString(md5.ComputeHash(Encoding.Default.GetBytes(sInputString))).Replace("-","");      return encoded;    }    /**//**//**//// <summary>    /// 获取文件的特征串    /// </summary>    /// <param name="sInputFilename">输入文件</param>    /// <returns></returns>    public string HashFile(string sInputFilename)...{      System.Security.Cryptography.MD5 md5 = System.Security.Cryptography.MD5.Create();      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();      string encoded = BitConverter.ToString(md5.ComputeHash(bInput)).Replace("-","");      return encoded;    }  }  /**//**//**//// <summary>  /// Base64 UUEncoded 编码  /// 将二进制编码为ASCII文本，用于网络传输  /// (可还原)  /// </summary>  public class BASE64...{    public BASE64()...{    }    /**//**//**//// <summary>    /// 解码字符串    /// </summary>    /// <param name="sInputString">输入文本</param>    /// <returns></returns>    public string DecryptString(string sInputString)...{      char[] sInput = sInputString.ToCharArray();      try...{        byte[] bOutput = System.Convert.FromBase64String(sInputString);        return Encoding.Default.GetString(bOutput);      }      catch ( System.ArgumentNullException ) ...{        //base 64 字符数组为null        return "";      }      catch ( System.FormatException ) ...{        //长度错误，无法整除4        return "";      }          }    /**//**//**//// <summary>    /// 编码字符串    /// </summary>    /// <param name="sInputString">输入文本</param>    /// <returns></returns>    public string EncryptString(string sInputString)...{      byte[] bInput = Encoding.Default.GetBytes(sInputString);      try ...{        return System.Convert.ToBase64String(bInput,0,bInput.Length);      }      catch (System.ArgumentNullException) ...{        //二进制数组为NULL.        return "";      }      catch (System.ArgumentOutOfRangeException) ...{        //长度不够        return "";      }    }    /**//**//**//// <summary>    /// 解码文件    /// </summary>    /// <param name="sInputFilename">输入文件</param>    /// <param name="sOutputFilename">输出文件</param>    public void DecryptFile(string sInputFilename,string sOutputFilename) ...{      System.IO.StreamReader inFile;           char[] base64CharArray;      try ...{        inFile = new System.IO.StreamReader(sInputFilename,          System.Text.Encoding.ASCII);        base64CharArray = new char[inFile.BaseStream.Length];        inFile.Read(base64CharArray, 0, (int)inFile.BaseStream.Length);        inFile.Close();      }      catch ...{//(System.Exception exp) {        return;      }      // 转换Base64 UUEncoded为二进制输出      byte[] binaryData;      try ...{        binaryData =           System.Convert.FromBase64CharArray(base64CharArray,          0,          base64CharArray.Length);      }      catch ( System.ArgumentNullException ) ...{        //base 64 字符数组为null        return;      }      catch ( System.FormatException ) ...{        //长度错误，无法整除4        return;      }      // 写输出数据      System.IO.FileStream outFile;      try ...{        outFile = new System.IO.FileStream(sOutputFilename,          System.IO.FileMode.Create,          System.IO.FileAccess.Write);        outFile.Write(binaryData, 0, binaryData.Length);        outFile.Close();      }      catch...{// (System.Exception exp) {        //流错误      }    }    /**//**//**//// <summary>    /// 编码文件    /// </summary>    /// <param name="sInputFilename">输入文件</param>    /// <param name="sOutputFilename">输出文件</param>    public void EncryptFile(string sInputFilename,string sOutputFilename)...{      System.IO.FileStream inFile;           byte[]                 binaryData;      try ...{        inFile = new System.IO.FileStream(sInputFilename,          System.IO.FileMode.Open,          System.IO.FileAccess.Read);        binaryData = new Byte[inFile.Length];        long bytesRead = inFile.Read(binaryData, 0,          (int) inFile.Length);        inFile.Close();      }      catch ...{ //(System.Exception exp) {        return;      }      // 转换二进制输入为Base64 UUEncoded输出      // 每3个字节在源数据里作为4个字节       long arrayLength = (long) ((4.0d/3.0d) * binaryData.Length);          // 如果无法整除4      if (arrayLength % 4 != 0) ...{        arrayLength += 4 - arrayLength % 4;      }          char[] base64CharArray = new char[arrayLength];      try ...{        System.Convert.ToBase64CharArray(binaryData,           0,          binaryData.Length,          base64CharArray,          0);      }      catch (System.ArgumentNullException) ...{        //二进制数组为NULL.        return;      }      catch (System.ArgumentOutOfRangeException) ...{        //长度不够        return;      }      // 写UUEncoded数据到文件内      System.IO.StreamWriter outFile;       try ...{        outFile = new System.IO.StreamWriter(sOutputFilename,          false,          System.Text.Encoding.ASCII);                     outFile.Write(base64CharArray);        outFile.Close();      }      catch...{// (System.Exception exp) {        //文件流出错      }     }  }  /**//**//**//// <summary>  /// DES 加密  /// 支持Key(钥匙)加密变化  /// 支持还原  ///   /// 演示操作：  ///  // 64位，8个字节  ///  string sSecretKey;  ///  ///  // 获取Key  ///  sSecretKey = GenerateKey();  ///  ///  // 托管  ///  GCHandle gch = GCHandle.Alloc( sSecretKey,GCHandleType.Pinned );  ///  ///  // 加密文件  ///  EncryptFile(@"C:MyData.txt",  ///  @"C:Encrypted.txt",  ///  sSecretKey);  ///  ///  // 解密文件  ///  DecryptFile(@"C:Encrypted.txt",  ///  @"C:Decrypted.txt",  ///  sSecretKey);  ///  ///  // 释放托管内容  ///  ZeroMemory(gch.AddrOfPinnedObject(), sSecretKey.Length * 2);  ///  gch.Free();  /// </summary>  public class DES ...{    [DllImport("KERNEL32.DLL", EntryPoint="RtlZeroMemory")]    public static extern bool ZeroMemory(IntPtr Destination, int Length);    public DES() ...{      //      // TODO: 在此处添加构造函数逻辑      //    }    /**//**//**//// <summary>    /// 创建Key    /// </summary>    /// <returns></returns>    public string GenerateKey() ...{      // 创建一个DES 算法的实例。自动产生Key      DESCryptoServiceProvider desCrypto =(DESCryptoServiceProvider)DESCryptoServiceProvider.Create();      // 返回自动创建的Key 用于加密      return ASCIIEncoding.ASCII.GetString(desCrypto.Key);    }    /**//**//**//// <summary>    /// 加密字符串    /// </summary>    /// <param name="sInputString">输入字符</param>    /// <param name="sKey">Key</param>    /// <returns>加密结果</returns>    public string EncryptString(string sInputString,string sKey)...{      byte[] data = Encoding.Default.GetBytes(sInputString);      byte[] result;      DESCryptoServiceProvider DES = new DESCryptoServiceProvider();      DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);      DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);      ICryptoTransform desencrypt = DES.CreateEncryptor();      result = desencrypt.TransformFinalBlock(data,0,data.Length);      string desString = "";      for(int i=0;i<result.Length;i++)...{        desString += result[i].ToString() + "-";      }            //return desString.TrimEnd('-');      return BitConverter.ToString(result);    }    /**//**//**//// <summary>    /// 解密字符串    /// </summary>    /// <param name="sInputString">输入字符</param>    /// <param name="sKey">Key</param>    /// <returns>解密结果</returns>    public string DecryptString(string sInputString,string sKey)...{      string[] sInput = sInputString.Split("-".ToCharArray());      byte[] data = new byte[sInput.Length];      byte[] result;      for(int i=0;i<sInput.Length;i++)        data[i] = byte.Parse(sInput[i],System.Globalization.NumberStyles.HexNumber);      DESCryptoServiceProvider DES = new DESCryptoServiceProvider();      DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);      DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);      ICryptoTransform desencrypt = DES.CreateDecryptor();      result = desencrypt.TransformFinalBlock(data,0,data.Length);      return Encoding.Default.GetString(result);    }    /**//**//**//// <summary>    /// 加密文件    /// </summary>    /// <param name="sInputFilename">输入文件</param>    /// <param name="sOutputFilename">输出文件</param>    /// <param name="sKey">Key</param>    public void EncryptFile(string sInputFilename,      string sOutputFilename,      string sKey) ...{      FileStream fsInput = new FileStream(sInputFilename,        FileMode.Open,        FileAccess.Read);      FileStream fsEncrypted = new FileStream(sOutputFilename,        FileMode.Create,        FileAccess.Write);      DESCryptoServiceProvider DES = new DESCryptoServiceProvider();      DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);      DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);      ICryptoTransform desencrypt = DES.CreateEncryptor();      CryptoStream cryptostream = new CryptoStream(fsEncrypted,        desencrypt,        CryptoStreamMode.Write);      byte[] bytearrayinput = new byte[fsInput.Length];      fsInput.Read(bytearrayinput, 0, bytearrayinput.Length);      cryptostream.Write(bytearrayinput, 0, bytearrayinput.Length);      cryptostream.Close();      fsInput.Close();      fsEncrypted.Close();    }    /**//**//**//// <summary>    /// 解密文件    /// </summary>    /// <param name="sInputFilename">输入文件</param>    /// <param name="sOutputFilename">输出文件</param>    /// <param name="sKey">Key</param>    public void DecryptFile(string sInputFilename,      string sOutputFilename,      string sKey) ...{      DESCryptoServiceProvider DES = new DESCryptoServiceProvider();      DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);      DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);      FileStream fsread = new FileStream(sInputFilename,        FileMode.Open,        FileAccess.Read);      ICryptoTransform desdecrypt = DES.CreateDecryptor();      CryptoStream cryptostreamDecr = new CryptoStream(fsread,        desdecrypt,        CryptoStreamMode.Read);      StreamWriter fsDecrypted = new StreamWriter(sOutputFilename);      fsDecrypted.Write(new StreamReader(cryptostreamDecr).ReadToEnd());      fsDecrypted.Flush();      fsDecrypted.Close();    }  }}