public static string aesDecode(string data, string key, string salt) {
    byte[]             salt2              = Encoding.UTF8.GetBytes(salt);
    Aes                aes                = new AesManaged();
    Rfc2898DeriveBytes rfc2898DeriveBytes = new Rfc2898DeriveBytes(key, salt2);
	
    aes.Key = rfc2898DeriveBytes.GetBytes(16);
    aes.IV  = aes.Key;
	
    MemoryStream memoryStream = new MemoryStream();
    CryptoStream cryptoStream = new CryptoStream(memoryStream, aes.CreateDecryptor(), CryptoStreamMode.Write);
    byte[]       bytes        = Convert.FromBase64String(data);
	
    cryptoStream.Write(bytes, 0, bytes.Length);
    cryptoStream.FlushFinalBlock();
	
    return Encoding.UTF8.GetString(memoryStream.ToArray());
}

public static string base64Decode(string data) {
    return Encoding.UTF8.GetString(Convert.FromBase64String(data));
}