Encryption and Decryption of data using a symmetric key ( Rijndael algorithm ) in C#?

There are several ways to encrypt and decrypt data but here i am going to use  symmetric key ( Rijndael algorithm ) Rijndael class found in namespace called System.Security.Cryptography.

Here is the code  with comment inline for understanding.

[java]

using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

namespace EncryptionDecrytion
{
class Program
{
static void Main(string[] args)
{
const string inputText = "abcs";
Console.WriteLine("Original string :-- " + inputText);
string enryptedText = SymmetricCryptor.Encrypt(inputText);
Console.WriteLine("Encrypted text :-- "+enryptedText);

string decryptedText = SymmetricCryptor.Decrypt(enryptedText);
Console.WriteLine("Decrypted text :-- " + decryptedText);

Console.ReadLine();
}
}

public class SymmetricCryptor
{
private const string ENCRYPTION_KEY = "123456";

#region Encryption/decryption

/// <summary>
/// The salt value used to strengthen the encryption.
/// </summary>
private static readonly byte[] Salt = Encoding.ASCII.GetBytes(ENCRYPTION_KEY.Length.ToString());

/// <summary>
/// Encrypts any string using the Rijndael algorithm.
/// </summary>
/// <param name="inputText">The string to encrypt.</param>
/// <returns>A Base64 encrypted string.</returns>
public static string Encrypt(string inputText)
{
var rijndaelCipher = new RijndaelManaged();
byte[] plainText = Encoding.Unicode.GetBytes(inputText.Replace(" ", "+"));
//Rfc2898DeriveBytes secretKey1 = new Rfc2898DeriveBytes(ENCRYPTION_KEY, SALT);
var SecretKey = new PasswordDeriveBytes(ENCRYPTION_KEY, Salt);
using (
ICryptoTransform encryptor = rijndaelCipher.CreateEncryptor(SecretKey.GetBytes(32),
SecretKey.GetBytes(16)))
using (var memoryStream = new MemoryStream())
{
using (var cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
{
cryptoStream.Write(plainText, 0, plainText.Length);
cryptoStream.FlushFinalBlock();
return Convert.ToBase64String(memoryStream.ToArray());
}
}
}

/// <summary>
/// Decrypts a previously encrypted string.
/// </summary>
/// <param name="inputText">The encrypted string to decrypt.</param>
/// <returns>A decrypted string.</returns>
public static string Decrypt(string inputText)
{
var rijndaelCipher = new RijndaelManaged();
byte[] encryptedData = Convert.FromBase64String(inputText);
//Rfc2898DeriveBytes secretKey1 = new Rfc2898DeriveBytes(ENCRYPTION_KEY, SALT);
var secretKey = new PasswordDeriveBytes(ENCRYPTION_KEY, Salt);
using (
ICryptoTransform decryptor = rijndaelCipher.CreateDecryptor(secretKey.GetBytes(32),
secretKey.GetBytes(16)))
{
using (var memoryStream = new MemoryStream(encryptedData))
{
using (var cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read))
{
var plainText = new byte[encryptedData.Length];
int decryptedCount = cryptoStream.Read(plainText, 0, plainText.Length);
return Encoding.Unicode.GetString(plainText, 0, decryptedCount).Replace("+", " ");
}
}
}
}

#endregion
}
}
[/java]

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