xml与DataSet的互转换类

以前在博客上发过，经人提醒DataSet已自带读写XML的功能，于是便删了，

不过在实践中感觉封装一层后，使用起来还是蛮方便的。故再次重发。

using System;

using System.Collections.Generic;

using System.Text;

using System.Data;

using System.IO;

using System.Xml;

namespace XmlDesign

{

    class XmlDatasetConvert

        //将xml对象内容字符串转换为DataSet

        public static DataSet ConvertXMLToDataSet(string xmlData)

            StringReader stream = null;

            XmlTextReader reader = null;

            try

                DataSet xmlDS = new DataSet();

                stream = new StringReader(xmlData);

                //从stream装载到XmlTextReader

                reader = new XmlTextReader(stream);

                xmlDS.ReadXml(reader);

                return xmlDS;

            }

            catch (System.Exception ex)

                throw ex;

            finally

                if (reader != null) reader.Close();

        }

        //将xml文件转换为DataSet

        public static DataSet ConvertXMLFileToDataSet(string xmlFile)

                XmlDocument xmld = new XmlDocument();

                xmld.Load(xmlFile);

                stream = new StringReader(xmld.InnerXml);

                //xmlDS.ReadXml(xmlFile);

        //将DataSet转换为xml对象字符串

        public static string ConvertDataSetToXML(DataSet xmlDS)

            MemoryStream stream = null;

            XmlTextWriter writer = null;

                stream = new MemoryStream();

                writer = new XmlTextWriter(stream, Encoding.Unicode);

                //用WriteXml方法写入文件.

                xmlDS.WriteXml(writer);

                int count = (int)stream.Length;

                byte[] arr = new byte[count];

                stream.Seek(0, SeekOrigin.Begin);

                stream.Read(arr, 0, count);

                UnicodeEncoding utf = new UnicodeEncoding();

                return utf.GetString(arr).Trim();

                if (writer != null) writer.Close();

        //将DataSet转换为xml文件

        public static void ConvertDataSetToXMLFile(DataSet xmlDS,string xmlFile)

                //返回Unicode编码的文本

                StreamWriter sw = new StreamWriter(xmlFile);

                sw.WriteLine("<?xml version=\"1.0\" encoding=\"utf-8\"?>");

                sw.WriteLine(utf.GetString(arr).Trim());

                sw.Close();

            catch( System.Exception ex )

    }

}