Encryption and Decription

using System;

using System.Data;

using System.Configuration;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;
using System.Xml;using System.Text;

using System.Security.Cryptography;

using System.IO;using System.Data.SqlClient;
public partial class _Default : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{

string str= Encrypt("Silpa");

SqlConnection con = new SqlConnection("Data Source=INFO-9;Initial Catalog=test;Integrated Security=True");

SqlCommand cmd=new SqlCommand("insert into pwdd values('"+str+"')",con);

con.Open();

cmd.ExecuteNonQuery();

con.Close();

string str1 = Decrypt("88tlfz/eGbtHNKDnXU6gQw==");

}
public static string Decrypt(string TextToBeDecrypted)

{

RijndaelManaged RijndaelCipher = new RijndaelManaged();
string Password = "CSC";

string DecryptedData;
try {

byte[] EncryptedData = Convert.FromBase64String(TextToBeDecrypted);
byte[] Salt = Encoding.ASCII.GetBytes(Password.Length.ToString());

//Making of the key for decryption

PasswordDeriveBytes SecretKey = new PasswordDeriveBytes(Password, Salt);

//Creates a symmetric Rijndael decryptor object.

ICryptoTransform Decryptor = RijndaelCipher.CreateDecryptor(SecretKey.GetBytes(32), SecretKey.GetBytes(16));
MemoryStream memoryStream = new MemoryStream(EncryptedData);

//Defines the cryptographics stream for decryption.THe stream contains decrpted data

CryptoStream cryptoStream = new CryptoStream(memoryStream, Decryptor, CryptoStreamMode.Read);
byte[] PlainText = new byte[EncryptedData.Length];

int DecryptedCount = cryptoStream.Read(PlainText, 0, PlainText.Length); memoryStream.Close();

cryptoStream.Close();
//Converting to string

DecryptedData = Encoding.Unicode.GetString(PlainText, 0, DecryptedCount);

}

catch

{

DecryptedData = TextToBeDecrypted;

}

return DecryptedData;

}
public static string Encrypt(string TextToBeEncrypted)

{

RijndaelManaged RijndaelCipher = new RijndaelManaged();

string Password = "CSC";

byte[] PlainText = System.Text.Encoding.Unicode.GetBytes(TextToBeEncrypted);

byte[] Salt = Encoding.ASCII.GetBytes(Password.Length.ToString()); PasswordDeriveBytes SecretKey = new PasswordDeriveBytes(Password, Salt);

//Creates a symmetric encryptor object.

ICryptoTransform Encryptor = RijndaelCipher.CreateEncryptor(SecretKey.GetBytes(32), SecretKey.GetBytes(16));

MemoryStream memoryStream = new MemoryStream();

//Defines a stream that links data streams to cryptographic transformations CryptoStream cryptoStream = new CryptoStream(memoryStream, Encryptor, CryptoStreamMode.Write);

cryptoStream.Write(PlainText, 0, PlainText.Length);

//Writes the final state and clears the buffer

cryptoStream.FlushFinalBlock();

byte[] CipherBytes = memoryStream.ToArray();

memoryStream.Close();

cryptoStream.Close();

string EncryptedData = Convert.ToBase64String(CipherBytes);
return EncryptedData;

}
}