Visual Basic

// generates the unique (salted) hash of a string
private static string getKey(string sSalt, string sKey)
{
    Byte[] originalBytes, encodedBytes;
    MD5 hash = new MD5CryptoServiceProvider();
    // or: SHA256 hash = new SHA256CryptoServiceProvider();

    // generate the hash value
    originalBytes = ASCIIEncoding.Default.GetBytes(sSalt + "." + sKey);
    encodedBytes = hash.ComputeHash(originalBytes);

    // turn the hash to a string and return it
    string sResult = BitConverter.ToString(encodedBytes).Replace("-", "");
    // or: string sResult = Convert.ToBase64String(encodedBytes);
    return sResult;
}

string hashValue = getKey(userName, userPass);

// Encrypt the given string using AES.  The string can be decrypted using 
// DecryptString().  The sharedSecret parameters must match.
public string EncryptString(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
        Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, this._salt);

        // Create a RijndaelManaged object
        aesAlg = new RijndaelManaged();
        aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);

        // Create a decrytor to perform the stream transform.
        ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

        // Create the streams used for encryption.
        using (MemoryStream msEncrypt = new MemoryStream())
        {
            // prepend the IV
            msEncrypt.Write(BitConverter.GetBytes(aesAlg.IV.Length), 0, sizeof(int));
            msEncrypt.Write(aesAlg.IV, 0, aesAlg.IV.Length);
            using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
            {
                using (StreamWriter 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;
}

// Decrypt the given string.  Assumes the string was encrypted using 
// EncryptString(), using an identical sharedSecret.
public string DecryptString(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
        Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, this._salt);

        // Create the streams used for decryption.                
        byte[] bytes = Convert.FromBase64String(cipherText);
        using (MemoryStream msDecrypt = new MemoryStream(bytes))
        {
            // Create a RijndaelManaged object
            // with the specified key and IV.
            aesAlg = new RijndaelManaged();
            aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);
            // Get the initialization vector from the encrypted stream
            aesAlg.IV = ReadByteArray(msDecrypt);
            // Create a decrytor to perform the stream transform.
            ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
            using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
            {
                using (StreamReader 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;
}

Protected Overrides Function ProcessCmdKey(ByRef msg As Message, keyData As Keys) As Boolean
  If activeBrick IsNot Nothing Then
    If keyData = Keys.Down OrElse keyData = Keys.Up Then
      MoveBrick(keyData)
      Return True
    End If
  End If
  Return MyBase.ProcessCmdKey(msg, keyData)
End Function

Private Function MoveBrick(ByVal keyData As Keys) As Boolean
    Dim oldLocation As Drawing.Point = activeBrick.Location
    Dim newLocation As Drawing.Point = oldLocation

    Select Case keyData
        Case Is = Keys.Up
            newLocation.Y = oldLocation.Y - 1
        Case Is = Keys.Down
            newLocation.Y = oldLocation.Y + 1
        Case Is = Keys.Left
            newLocation.X = oldLocation.X - 1
        Case Is = Keys.Right
            newLocation.X = oldLocation.X + 1
    End Select

    activeBrick.Location = newLocation
    Return True

End Function