public void GenerateErrorResponse(int number, string message, XmlWriter writer)
{
writer.WriteStartElement("response");
if (number > 0) {
writer.WriteElementString("error", number.ToString());
}
if (!string.IsNullOrEmpty(message)) {
writer.WriteElementString("message", message);
}
writer.WriteEndElement();
writer.Flush();
writer.Close();
}