C#加密解密(DES,AES,Base64,md5,SHA256,RSA,RC4)

一:异或^简单加解密(数字类型)

1:原理:

异或用于比较两个二进制数的相应位,在执行按位"异或"运算时,如果两个二进制数的相应位都为1或者都为0,则返回0;如果两个二进制数的相应位其中一个为1另一个为0,则返回1.

//对数字加密 int P_int_Num, P_int_Key;//定义两个值类型变量string Encryptstr = (P_int_Num ^ P_int_Key).ToString();//加密数值//对数字解密 int P_int_Key, P_int_Encrypt;//定义两个值类型变量string Encryptstr =(P_int_Encrypt ^ P_int_Key).ToString();//解密数值

二:加密解密类

(DES,AES,Base64,md5,SHA256,RSA,RC4)

public class JiaMiJieMi  {    #region DES对称加密解密    /// <summary> 加密字符串    /// </summary>     /// <param name="strText">需被加密的字符串</param>     /// <param name="strEncrKey">密钥</param>     /// <returns></returns>     public static string DesEncrypt(string strText, string strEncrKey)    {      try      {        byte[] byKey = null;        byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };        byKey = Encoding.UTF8.GetBytes(strEncrKey.Substring(0, 8));        DESCryptoServiceProvider des = new DESCryptoServiceProvider();        byte[] inputByteArray = Encoding.UTF8.GetBytes(strText);        MemoryStream ms = new MemoryStream();        CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(byKey, IV), CryptoStreamMode.Write);        cs.Write(inputByteArray, 0, inputByteArray.Length);        cs.FlushFinalBlock();        return Convert.ToBase64String(ms.ToArray());      }      catch      {        return "";      }    }    /// <summary> 解密字符串    /// </summary>     /// <param name="strText">需被解密的字符串</param>     /// <param name="sDecrKey">密钥</param>     /// <returns></returns>     public static string DesDecrypt(string strText, string sDecrKey)    {      try      {        byte[] byKey = null;        byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };        byte[] inputByteArray = new Byte[strText.Length];        byKey = Encoding.UTF8.GetBytes(sDecrKey.Substring(0, 8));        DESCryptoServiceProvider des = new DESCryptoServiceProvider();        inputByteArray = Convert.FromBase64String(strText);        MemoryStream ms = new MemoryStream();        CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(byKey, IV), CryptoStreamMode.Write);        cs.Write(inputByteArray, 0, inputByteArray.Length);        cs.FlushFinalBlock();        Encoding encoding = new UTF8Encoding();        return encoding.GetString(ms.ToArray());      }      catch      {        return null;      }    }    /// <summary> 加密文件    ///    /// </summary>     /// <param name="m_InFilePath">原路径</param>     /// <param name="m_OutFilePath">加密后的文件路径</param>     /// <param name="strEncrKey">密钥</param>     public static void DesEncryptFile(string m_InFilePath, string m_OutFilePath, string strEncrKey)    {      try      {        byte[] byKey = null;        byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };        byKey = Encoding.UTF8.GetBytes(strEncrKey.Substring(0, 8));        FileStream fin = new FileStream(m_InFilePath, FileMode.Open, FileAccess.Read);        FileStream fout = new FileStream(m_OutFilePath, FileMode.OpenOrCreate, FileAccess.Write);        fout.SetLength(0);        //Create variables to help with read and write.         byte[] bin = new byte[100]; //This is intermediate storage for the encryption.         long rdlen = 0; //This is the total number of bytes written.         long totlen = fin.Length; //This is the total length of the input file.         int len; //This is the number of bytes to be written at a time.        DES des = new DESCryptoServiceProvider();        CryptoStream encStream = new CryptoStream(fout, des.CreateEncryptor(byKey, IV), CryptoStreamMode.Write);        //Read from the input file, then encrypt and write to the output file.         while (rdlen < totlen)        {          len = fin.Read(bin, 0, 100);          encStream.Write(bin, 0, len);          rdlen = rdlen + len;        }        encStream.Close();        fout.Close();        fin.Close();      }      catch      {      }          }    /// <summary> 解密文件    ///     /// </summary>     /// <param name="m_InFilePath">被解密路径</param>     /// <param name="m_OutFilePath">解密后的路径</param>     /// <param name="sDecrKey">密钥</param>     public static void DesDecryptFile(string m_InFilePath, string m_OutFilePath, string sDecrKey)    {      try      {        byte[] byKey = null;        byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };        byKey = Encoding.UTF8.GetBytes(sDecrKey.Substring(0, 8));        FileStream fin = new FileStream(m_InFilePath, FileMode.Open, FileAccess.Read);        FileStream fout = new FileStream(m_OutFilePath, FileMode.OpenOrCreate, FileAccess.Write);        fout.SetLength(0);        //Create variables to help with read and write.         byte[] bin = new byte[100]; //This is intermediate storage for the encryption.         long rdlen = 0; //This is the total number of bytes written.         long totlen = fin.Length; //This is the total length of the input file.         int len; //This is the number of bytes to be written at a time.        DES des = new DESCryptoServiceProvider();        CryptoStream encStream = new CryptoStream(fout, des.CreateDecryptor(byKey, IV), CryptoStreamMode.Write);        //Read from the input file, then encrypt and write to the output file.         while (rdlen < totlen)        {          len = fin.Read(bin, 0, 100);          encStream.Write(bin, 0, len);          rdlen = rdlen + len;        }        encStream.Close();        fout.Close();        fin.Close();      }      catch      {      }    }    #endregion    #region 

    private static readonly string Default_AES_Key = "@#kim123";    private static byte[] Keys = { 0x41, 0x72, 0x65, 0x79, 0x6F, 0x75, 0x6D, 0x79,                       0x53,0x6E, 0x6F, 0x77, 0x6D, 0x61, 0x6E, 0x3F };    public static string AES_Encrypt(string encryptString)    {      return AES_Encrypt(encryptString, Default_AES_Key);    }    public static string AES_Decrypt(string decryptString)    {      return AES_Decrypt(decryptString, Default_AES_Key);    }    /// <summary>对称加密算法AES RijndaelManaged加密(RijndaelManaged（AES）算法是块式加密算法)    ///     /// </summary>    /// <param name="encryptString">待加密字符串</param>    /// <param name="encryptKey">加密密钥，须半角字符</param>    /// <returns>加密结果字符串</returns>    public static string AES_Encrypt(string encryptString, string encryptKey)    {      encryptKey = GetSubString(encryptKey, 32, "");      encryptKey = encryptKey.PadRight(32, ' ');      RijndaelManaged rijndaelProvider = new RijndaelManaged();      rijndaelProvider.Key = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 32));      rijndaelProvider.IV = Keys;      ICryptoTransform rijndaelEncrypt = rijndaelProvider.CreateEncryptor();      byte[] inputData = Encoding.UTF8.GetBytes(encryptString);      byte[] encryptedData = rijndaelEncrypt.TransformFinalBlock(inputData, 0, inputData.Length);      return Convert.ToBase64String(encryptedData);    }    /// <summary> 对称加密算法AES RijndaelManaged解密字符串    ///    /// </summary>    /// <param name="decryptString">待解密的字符串</param>    /// <param name="decryptKey">解密密钥,和加密密钥相同</param>    /// <returns>解密成功返回解密后的字符串,失败返回空</returns>    public static string AES_Decrypt(string decryptString, string decryptKey)    {      try      {        decryptKey = GetSubString(decryptKey, 32, "");        decryptKey = decryptKey.PadRight(32, ' ');        RijndaelManaged rijndaelProvider = new RijndaelManaged();        rijndaelProvider.Key = Encoding.UTF8.GetBytes(decryptKey);        rijndaelProvider.IV = Keys;        ICryptoTransform rijndaelDecrypt = rijndaelProvider.CreateDecryptor();        byte[] inputData = Convert.FromBase64String(decryptString);        byte[] decryptedData = rijndaelDecrypt.TransformFinalBlock(inputData, 0, inputData.Length);        return Encoding.UTF8.GetString(decryptedData);      }      catch      {        return string.Empty;      }    }    /// <summary>    /// 按字节长度(按字节,一个汉字为2个字节)取得某字符串的一部分    /// </summary>    /// <param name="sourceString">源字符串</param>    /// <param name="length">所取字符串字节长度</param>    /// <param name="tailString">附加字符串(当字符串不够长时，尾部所添加的字符串，一般为"...")</param>    /// <returns>某字符串的一部分</returns>    private static string GetSubString(string sourceString, int length, string tailString)    {      return GetSubString(sourceString, 0, length, tailString);    }    /// <summary>    /// 按字节长度(按字节,一个汉字为2个字节)取得某字符串的一部分    /// </summary>    /// <param name="sourceString">源字符串</param>    /// <param name="startIndex">索引位置，以0开始</param>    /// <param name="length">所取字符串字节长度</param>    /// <param name="tailString">附加字符串(当字符串不够长时，尾部所添加的字符串，一般为"...")</param>    /// <returns>某字符串的一部分</returns>    private static string GetSubString(string sourceString, int startIndex, int length, string tailString)    {      string myResult = sourceString;      //当是日文或韩文时(注:中文的范围:\u4e00 - \u9fa5, 日文在\u0800 - \u4e00, 韩文为\xAC00-\xD7A3)      if (System.Text.RegularExpressions.Regex.IsMatch(sourceString, "[\u0800-\u4e00]+") ||        System.Text.RegularExpressions.Regex.IsMatch(sourceString, "[\xAC00-\xD7A3]+"))      {        //当截取的起始位置超出字段串长度时        if (startIndex >= sourceString.Length)        {          return string.Empty;        }        else        {          return sourceString.Substring(startIndex,                          ((length + startIndex) > sourceString.Length) ? (sourceString.Length - startIndex) : length);        }      }      //中文字符，如"中国人民abcd123"      if (length <= 0)      {        return string.Empty;      }      byte[] bytesSource = Encoding.Default.GetBytes(sourceString);      //当字符串长度大于起始位置      if (bytesSource.Length > startIndex)      {        int endIndex = bytesSource.Length;        //当要截取的长度在字符串的有效长度范围内        if (bytesSource.Length > (startIndex + length))        {          endIndex = length + startIndex;        }        else        {  //当不在有效范围内时,只取到字符串的结尾          length = bytesSource.Length - startIndex;          tailString = "";        }        int[] anResultFlag = new int[length];        int nFlag = 0;        //字节大于127为双字节字符        for (int i = startIndex; i < endIndex; i++)        {          if (bytesSource[i] > 127)          {            nFlag++;            if (nFlag == 3)            {              nFlag = 1;            }          }          else          {            nFlag = 0;          }          anResultFlag[i] = nFlag;        }        //最后一个字节为双字节字符的一半        if ((bytesSource[endIndex - 1] > 127) && (anResultFlag[length - 1] == 1))        {          length = length + 1;        }        byte[] bsResult = new byte[length];        Array.Copy(bytesSource, startIndex, bsResult, 0, length);        myResult = Encoding.Default.GetString(bsResult);        myResult = myResult + tailString;        return myResult;      }      return string.Empty;    }    /// <summary>    /// 加密文件流    /// </summary>    /// <param name="fs"></param>    /// <returns></returns>    public static CryptoStream AES_EncryptStrream(FileStream fs, string decryptKey)    {      decryptKey = GetSubString(decryptKey, 32, "");      decryptKey = decryptKey.PadRight(32, ' ');      RijndaelManaged rijndaelProvider = new RijndaelManaged();      rijndaelProvider.Key = Encoding.UTF8.GetBytes(decryptKey);      rijndaelProvider.IV = Keys;      ICryptoTransform encrypto = rijndaelProvider.CreateEncryptor();      CryptoStream cytptostreamEncr = new CryptoStream(fs, encrypto, CryptoStreamMode.Write);      return cytptostreamEncr;    }    /// <summary>    /// 解密文件流    /// </summary>    /// <param name="fs"></param>    /// <returns></returns>    public static CryptoStream AES_DecryptStream(FileStream fs, string decryptKey)    {      decryptKey = GetSubString(decryptKey, 32, "");      decryptKey = decryptKey.PadRight(32, ' ');      RijndaelManaged rijndaelProvider = new RijndaelManaged();      rijndaelProvider.Key = Encoding.UTF8.GetBytes(decryptKey);      rijndaelProvider.IV = Keys;      ICryptoTransform Decrypto = rijndaelProvider.CreateDecryptor();      CryptoStream cytptostreamDecr = new CryptoStream(fs, Decrypto, CryptoStreamMode.Read);      return cytptostreamDecr;    }    /// <summary>    /// 对指定文件加密    /// </summary>    /// <param name="InputFile"></param>    /// <param name="OutputFile"></param>    /// <returns></returns>    public static bool AES_EncryptFile(string InputFile, string OutputFile)    {      try      {        string decryptKey = "www.iqidi.com";        FileStream fr = new FileStream(InputFile, FileMode.Open);        FileStream fren = new FileStream(OutputFile, FileMode.Create);        CryptoStream Enfr = AES_EncryptStrream(fren, decryptKey);        byte[] bytearrayinput = new byte[fr.Length];        fr.Read(bytearrayinput, 0, bytearrayinput.Length);        Enfr.Write(bytearrayinput, 0, bytearrayinput.Length);        Enfr.Close();        fr.Close();        fren.Close();      }      catch      {        //文件异常        return false;      }      return true;    }    /// <summary>    /// 对指定的文件解压缩    /// </summary>    /// <param name="InputFile"></param>    /// <param name="OutputFile"></param>    /// <returns></returns>    public static bool AES_DecryptFile(string InputFile, string OutputFile)    {      try      {        string decryptKey = "www.iqidi.com";        FileStream fr = new FileStream(InputFile, FileMode.Open);        FileStream frde = new FileStream(OutputFile, FileMode.Create);        CryptoStream Defr = AES_DecryptStream(fr, decryptKey);        byte[] bytearrayoutput = new byte[1024];        int m_count = 0;        do        {          m_count = Defr.Read(bytearrayoutput, 0, bytearrayoutput.Length);          frde.Write(bytearrayoutput, 0, m_count);          if (m_count < bytearrayoutput.Length)            break;        } while (true);        Defr.Close();        fr.Close();        frde.Close();      }      catch      {        //文件异常        return false;      }      return true;    }    #endregion    #region Base64加密解密    /// <summary>    /// Base64是一種使用64基的位置計數法。它使用2的最大次方來代表僅可列印的ASCII 字元。    /// 這使它可用來作為電子郵件的傳輸編碼。在Base64中的變數使用字元A-Z、a-z和0-9 ，    /// 這樣共有62個字元，用來作為開始的64個數字，最後兩個用來作為數字的符號在不同的    /// 系統中而不同。    /// Base64加密    /// </summary>    /// <param name="str"></param>    /// <returns></returns>    public static string Base64Encrypt(string str)    {      byte[] encbuff = System.Text.Encoding.UTF8.GetBytes(str);      return Convert.ToBase64String(encbuff);    }    /// <summary>    /// Base64解密    /// </summary>    /// <param name="str"></param>    /// <returns></returns>    public static string Base64Decrypt(string str)    {      byte[] decbuff = Convert.FromBase64String(str);      return System.Text.Encoding.UTF8.GetString(decbuff);    }    #endregion    #region md5     /// <summary>    /// 获得32位的MD5加密    /// </summary>    /// <param name="input"></param>    /// <returns></returns>    public static string GetMD5_32(string input)    {      System.Security.Cryptography.MD5 md5 = System.Security.Cryptography.MD5.Create();      byte[] data = md5.ComputeHash(System.Text.Encoding.Default.GetBytes(input));      StringBuilder sb = new StringBuilder();      for (int i = 0; i < data.Length; i++)      {        sb.Append(data[i].ToString("x2"));      }      return sb.ToString();    }    /// <summary>    /// 获得16位的MD5加密    /// </summary>    /// <param name="input"></param>    /// <returns></returns>    public static string GetMD5_16(string input)    {      return GetMD5_32(input).Substring(8, 16);    }    /// <summary>    /// 获得8位的MD5加密    /// </summary>    /// <param name="input"></param>    /// <returns></returns>    public static string GetMD5_8(string input)    {      return GetMD5_32(input).Substring(8, 8);    }    /// <summary>    /// 获得4位的MD5加密    /// </summary>    /// <param name="input"></param>    /// <returns></returns>    public static string GetMD5_4(string input)    {      return GetMD5_32(input).Substring(8, 4);    }    public static string MD5EncryptHash(String input)    {      MD5 md5 = new MD5CryptoServiceProvider();      //the GetBytes method returns byte array equavalent of a string      byte[] res = md5.ComputeHash(Encoding.Default.GetBytes(input), 0, input.Length);      char[] temp = new char[res.Length];      //copy to a char array which can be passed to a String constructor      Array.Copy(res, temp, res.Length);      //return the result as a string      return new String(temp);    }    #endregion    #region MD5签名验证    /// <summary>    /// 对给定文件路径的文件加上标签    /// </summary>    /// <param name="path">要加密的文件的路径</param>    /// <returns>标签的值</returns>    public static bool AddMD5(string path)    {      bool IsNeed = true;      if (CheckMD5(path))                 //已进行MD5处理        IsNeed = false;      try      {        FileStream fsread = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read);        byte[] md5File = new byte[fsread.Length];        fsread.Read(md5File, 0, (int)fsread.Length);                // 将文件流读取到Buffer中        fsread.Close();        if (IsNeed)        {          string result = MD5Buffer(md5File, 0, md5File.Length);       // 对Buffer中的字节内容算MD5          byte[] md5 = System.Text.Encoding.ASCII.GetBytes(result);    // 将字符串转换成字节数组以便写人到文件中          FileStream fsWrite = new FileStream(path, FileMode.Open, FileAccess.ReadWrite);          fsWrite.Write(md5File, 0, md5File.Length);                // 将文件，MD5值 重新写入到文件中。          fsWrite.Write(md5, 0, md5.Length);          fsWrite.Close();        }        else        {          FileStream fsWrite = new FileStream(path, FileMode.Open, FileAccess.ReadWrite);          fsWrite.Write(md5File, 0, md5File.Length);          fsWrite.Close();        }      }      catch      {        return false;      }      return true;    }    /// <summary>    /// 对给定路径的文件进行验证    /// </summary>    /// <param name="path"></param>    /// <returns>是否加了标签或是否标签值与内容值一致</returns>    public static bool CheckMD5(string path)    {      try      {        FileStream get_file = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read);        byte[] md5File = new byte[get_file.Length];                   // 读入文件        get_file.Read(md5File, 0, (int)get_file.Length);        get_file.Close();        string result = MD5Buffer(md5File, 0, md5File.Length - 32);       // 对文件除最后32位以外的字节计算MD5，这个32是因为标签位为32位。        string md5 = System.Text.Encoding.ASCII.GetString(md5File, md5File.Length - 32, 32);  //读取文件最后32位，其中保存的就是MD5值        return result == md5;      }      catch      {        return false;      }    }    /// <summary>    /// 计算文件的MD5值    /// </summary>    /// <param name="MD5File">MD5签名文件字符数组</param>    /// <param name="index">计算起始位置</param>    /// <param name="count">计算终止位置</param>    /// <returns>计算结果</returns>    private static string MD5Buffer(byte[] MD5File, int index, int count)    {      System.Security.Cryptography.MD5CryptoServiceProvider get_md5 = new System.Security.Cryptography.MD5CryptoServiceProvider();      byte[] hash_byte = get_md5.ComputeHash(MD5File, index, count);      string result = System.BitConverter.ToString(hash_byte);      result = result.Replace("-", "");      return result;    }    #endregion    #region SHA256加密算法        /// <summary>    /// SHA256函数    /// </summary>    /// <param name="str">原始字符串</param>    /// <returns>SHA256结果(返回长度为44字节的字符串)</returns>    public static string SHA256(string str)    {      byte[] SHA256Data = Encoding.UTF8.GetBytes(str);      SHA256Managed Sha256 = new SHA256Managed();      byte[] Result = Sha256.ComputeHash(SHA256Data);      return Convert.ToBase64String(Result); //返回长度为44字节的字符串    }    #endregion    #region 

    /// <summary>RSA加密    ///     /// </summary>    /// <param name="plaintext">明文</param>    /// <param name="publicKey">公钥</param>    /// <returns>密文字符串</returns>    public static string EncryptByRSA(string plaintext, string publicKey)    {      try      {        UnicodeEncoding ByteConverter = new UnicodeEncoding();        byte[] dataToEncrypt = ByteConverter.GetBytes(plaintext);        using (RSACryptoServiceProvider RSA = new RSACryptoServiceProvider())        {          RSA.Frombyte[] encryptedData = RSA.Encrypt(dataToEncrypt, false);          return Convert.ToBase64String(encryptedData);        }      }      catch (Exception)      {        return null;      }         }    /// <summary> RSA解密    ///    /// </summary>    /// <param name="ciphertext">密文</param>    /// <param name="privateKey">私钥</param>    /// <returns>明文字符串</returns>    public static string DecryptByRSA(string ciphertext, string privateKey)    {      try      {        UnicodeEncoding byteConverter = new UnicodeEncoding();        using (RSACryptoServiceProvider RSA = new RSACryptoServiceProvider())        {          RSA.Frombyte[] encryptedData = Convert.FromBase64String(ciphertext);          byte[] decryptedData = RSA.Decrypt(encryptedData, false);          return byteConverter.GetString(decryptedData);        }      }      catch (Exception)      {        return null;      }          }    /// <summary>生成RSA加密 解密的 密钥    /// 生成的key就是 方法EncryptByRSA与DecryptByRSA用的key了    /// </summary>    /// <param name="path">要生成的密钥文件的路径(文件夹)</param>    public static void getRSAKey(string path)    {      RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();      string datetimestr = System.DateTime.Now.ToString("yyyyMMddHHmmss");      using (StreamWriter writer = new StreamWriter("RSA解密_PrivateKey_" + datetimestr + ".")) //这个文件要保密...      {        writer.WriteLine(rsa.Totrue));      }      using (StreamWriter writer = new StreamWriter("RSA加密_PublicKey_" + datetimestr + "."))      {        writer.WriteLine(rsa.Tofalse));      }    }    #endregion    #region 

    /// <summary>RC4加密算法    /// 返回进过rc4加密过的字符    /// </summary>    /// <param name="str">被加密的字符</param>    /// <param name="ckey">密钥</param>    public static string EncryptRC4wq(string str, string ckey)    {      int[] s = new int[256];      for (int i = 0; i < 256; i++)      {        s[i] = i;      }      //密钥转数组      char[] keys = ckey.ToCharArray();//密钥转字符数组      int[] key = new int[keys.Length];      for (int i = 0; i < keys.Length; i++)      {        key[i] = keys[i];      }      //明文转数组      char[] datas = str.ToCharArray();      int[] mingwen = new int[datas.Length];      for (int i = 0; i < datas.Length; i++)      {        mingwen[i] = datas[i];      }      //通过循环得到256位的数组(密钥)      int j = 0;      int k = 0;      int length = key.Length;      int a;      for (int i = 0; i < 256; i++)      {        a = s[i];        j = (j + a + key[k]);        if (j >= 256)        {          j = j % 256;        }        s[i] = s[j];        s[j] = a;        if (++k >= length)        {          k = 0;        }      }      //根据上面的256的密钥数组 和 明文得到密文数组      int x = 0, y = 0, a2, b, c;      int length2 = mingwen.Length;      int[] miwen = new int[length2];      for (int i = 0; i < length2; i++)      {        x = x + 1;        x = x % 256;        a2 = s[x];        y = y + a2;        y = y % 256;        s[x] = b = s[y];        s[y] = a2;        c = a2 + b;        c = c % 256;        miwen[i] = mingwen[i] ^ s[c];      }      //密文数组转密文字符      char[] mi = new char[miwen.Length];      for (int i = 0; i < miwen.Length; i++)      {        mi[i] = (char)miwen[i];      }      string miwenstr = new string(mi);      return miwenstr;    }    /// <summary>RC4解密算法    /// 返回进过rc4解密过的字符    /// </summary>    /// <param name="str">被解密的字符</param>    /// <param name="ckey">密钥</param>    public static string DecryptRC4wq(string str, string ckey)    {      int[] s = new int[256];      for (int i = 0; i < 256; i++)      {        s[i] = i;      }      //密钥转数组      char[] keys = ckey.ToCharArray();//密钥转字符数组      int[] key = new int[keys.Length];      for (int i = 0; i < keys.Length; i++)      {        key[i] = keys[i];      }      //密文转数组      char[] datas = str.ToCharArray();      int[] miwen = new int[datas.Length];      for (int i = 0; i < datas.Length; i++)      {        miwen[i] = datas[i];      }      //通过循环得到256位的数组(密钥)      int j = 0;      int k = 0;      int length = key.Length;      int a;      for (int i = 0; i < 256; i++)      {        a = s[i];        j = (j + a + key[k]);        if (j >= 256)        {          j = j % 256;        }        s[i] = s[j];        s[j] = a;        if (++k >= length)        {          k = 0;        }      }      //根据上面的256的密钥数组 和 密文得到明文数组      int x = 0, y = 0, a2, b, c;      int length2 = miwen.Length;      int[] mingwen = new int[length2];      for (int i = 0; i < length2; i++)      {        x = x + 1;        x = x % 256;        a2 = s[x];        y = y + a2;        y = y % 256;        s[x] = b = s[y];        s[y] = a2;        c = a2 + b;        c = c % 256;        mingwen[i] = miwen[i] ^ s[c];      }      //明文数组转明文字符      char[] ming = new char[mingwen.Length];      for (int i = 0; i < mingwen.Length; i++)      {        ming[i] = (char)mingwen[i];      }      string mingwenstr = new string(ming);      return mingwenstr;    }    #endregion  }

数据加密解密详谈

原标题：C#加密解密(DES,AES,Base64,md5,SHA256,RSA,RC4)

关键词：C#