datata 和XML转换 3

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= newbyte[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;
        returnnull;
      }
      finally
      {
        if (reader!= null)
        reader.Close();
      }
    }