Converts a ADO.NET DataSet to an XML String.

private static string DataSetToXmlString(DataSet ds)
{
	StringBuilder stringBuilder = new StringBuilder();
	XmlTextWriter xmlTextWriter = new XmlTextWriter(new StringWriter(stringBuilder));
	xmlTextWriter.Formatting = Formatting.None;
	ds.WriteXml(xmlTextWriter);
	xmlTextWriter.Close();
	return stringBuilder.ToString();
}