简单的C# xml字符串转换dataset或者datatable
调用：
DataTable dt = XmlToDataSet(xmlText).Tables[0];

DataSet XmlToDataSet(string xml)
        {
            XmlDocument xmldoc = new XmlDocument();
            xmldoc.LoadXml(xml);
            StringReader stream = null;
            XmlTextReader reader = null;
            try
            {
                DataSet xmlDS = new DataSet();
                stream = new StringReader(xmldoc.InnerXml);
                reader = new XmlTextReader(stream);
                xmlDS.ReadXml(reader);
                reader.Close();
                stream.Close();
                stream.Dispose();

                return xmlDS;
            }
            catch (System.Exception ex)
            {
                reader.Close();
                throw ex;
            }
        }