DataSet(DataTable)与XML互转

using System;    using System.Data;    using System.IO;    using System.Xml;    using System.Text;    // 相应C#代码：    private string ConvertDataTableToXML(DataTable xmlDS)    {        MemoryStream stream = null;        XmlTextWriter writer = null;        try        {            stream = new MemoryStream();            writer = new XmlTextWriter(stream, Encoding.Default);            xmlDS.WriteXml(writer);            int count = (int)stream.Length;            byte[] arr = new byte[count];            stream.Seek(0, SeekOrigin.Begin);            stream.Read(arr, 0, count);            UTF8Encoding utf = new UTF8Encoding();            return utf.GetString(arr).Trim();        }        catch        {            return String.Empty;        }        finally        {            if (writer != null) writer.Close();        }    }     private DataSet ConvertXMLToDataSet(string xmlData)    {      StringReader stream = null;      XmlTextReader reader = null;      try      {        DataSet xmlDS = new DataSet();        stream = new StringReader(xmlData);        reader = new XmlTextReader(stream);        xmlDS.ReadXml(reader);        return xmlDS;      }      catch (Exception ex)      {        string strTest = ex.Message;        return null;      }      finally      {        if (reader != null)        reader.Close();      }    }