using System;

using System.Security.Cryptography;

​

public class DataProtectionSample

{

    // Create byte array for additional entropy when using Protect method.

    static byte [] s_additionalEntropy = { 9, 8, 7, 6, 5 };

​

    public static void Main()

    {

        // Create a simple byte array containing data to be encrypted.

        byte [] secret = { 0, 1, 2, 3, 4, 1, 2, 3, 4 };

​

        //Encrypt the data.

        byte [] encryptedSecret = Protect( secret );

        Console.WriteLine("The encrypted byte array is:");

        PrintValues(encryptedSecret);

​

        // Decrypt the data and store in a byte array.

        byte [] originalData = Unprotect( encryptedSecret );

        Console.WriteLine("{0}The original data is:", Environment.NewLine);

        PrintValues(originalData);

    }

​

    public static byte [] Protect( byte [] data )

    {

        try

        {

            // Encrypt the data using DataProtectionScope.CurrentUser. The result can be decrypted

            // only by the same current user.

            return ProtectedData.Protect( data, s_additionalEntropy, DataProtectionScope.CurrentUser );

        }

        catch (CryptographicException e)

        {

            Console.WriteLine("Data was not encrypted. An error occurred.");

            Console.WriteLine(e.ToString());

            return null;

        }

    }

​

    public static byte [] Unprotect( byte [] data )

    {

        try

        {

            //Decrypt the data using DataProtectionScope.CurrentUser.

            return ProtectedData.Unprotect( data, s_additionalEntropy, DataProtectionScope.CurrentUser );

        }

        catch (CryptographicException e)

        {

            Console.WriteLine("Data was not decrypted. An error occurred.");

            Console.WriteLine(e.ToString());

            return null;

        }

    }

​

    public static void PrintValues( Byte[] myArr )

    {

        foreach ( Byte i in myArr )

        {

            Console.Write( "\t{0}", i );

        }

        Console.WriteLine();

    }

}