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DecryptEncrypt String AES

using System; using System.Text; using System.Security.Cryptography; using System.IO; namespace OpusSuite.Utility {     public static class CryptoUtil     {        private static byte[] _salt = Encoding.ASCII.GetBytes("o6806642kbM7c5");                   public static string EncryptStringAES(string plainText, string sharedSecret)              {                      if(string.IsNullOrEmpty(plainText))                              throw new ArgumentNullException("plainText");                      if(string.IsNullOrEmpty(sharedSecret))                              throw new ArgumentNullException("sharedSecret");                       string outStr = null;                       // Encrypted string to return                      RijndaelManaged aesAlg = null;              // RijndaelManaged object used to encrypt the data.             try                      {                              // generate the key from the shared secret and the salt                              var key = new Rfc2898DeriveBytes(sharedSecret, _salt);                               // Create a RijndaelManaged object                              // with the specified key and IV.                              aesAlg = new RijndaelManaged();                              aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);                              aesAlg.IV = key.GetBytes(aesAlg.BlockSize / 8);                               // Create a decrytor to perform the stream transform.                              ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);                               // Create the streams used for encryption.                              using (var msEncrypt = new MemoryStream())                              {                                      using (var csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))                     {                                              using (var swEncrypt = new StreamWriter(csEncrypt))                                              {                                                       //Write all data to the stream.                                                      swEncrypt.Write(plainText);                                              }                                      }                                      outStr = Convert.ToBase64String(msEncrypt.ToArray());                              }                      }                      finally                      {                              // Clear the RijndaelManaged object.                              if (aesAlg != null)                                      aesAlg.Clear();                      }                       // Return the encrypted bytes from the memory stream.                      return outStr;              }                        public static string DecryptStringAES(string cipherText, string sharedSecret)              {                      if (string.IsNullOrEmpty(cipherText))                              throw new ArgumentNullException("cipherText");                      if (string.IsNullOrEmpty(sharedSecret))                              throw new ArgumentNullException("sharedSecret");                       // Declare the RijndaelManaged object                      // used to decrypt the data.                      RijndaelManaged aesAlg = null;                       // Declare the string used to hold                      // the decrypted text.                      string plaintext = null;                       try                      {                              // generate the key from the shared secret and the salt                              var key = new Rfc2898DeriveBytes(sharedSecret, _salt);                               // Create a RijndaelManaged object                              // with the specified key and IV.                              aesAlg = new RijndaelManaged();                              aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);                 aesAlg.IV = key.GetBytes(aesAlg.BlockSize / 8);                               // Create a decrytor to perform the stream transform.                              ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);                 // Create the streams used for decryption.                                              byte[] bytes = Convert.FromBase64String(cipherText);                              using (var msDecrypt = new MemoryStream(bytes))                              {                                      using (var csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))                                      {                                              using (var srDecrypt = new StreamReader(csDecrypt))                                                       // Read the decrypted bytes from the decrypting stream                                                      // and place them in a string.                                                      plaintext = srDecrypt.ReadToEnd();                                      }                              }                      }                      finally                      {                              // Clear the RijndaelManaged object.                              if (aesAlg != null)                                      aesAlg.Clear();                      }                       return plaintext;              }      }  }