DataSet与Xml文件的互相转换

DataSet转换为xml文件 
　　  //将DataSet转换为xml文件
        private static void ConvertDataSetToXMLFile(DataSet xmlDS, string xmlFile)
        {
            MemoryStream stream = null;
            XmlTextWriter writer = null;
            
            try
            {
                stream = new MemoryStream();
                //从stream装载到XmlTextReader
                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);

                //返回Unicode编码的文本
                UnicodeEncoding utf = new UnicodeEncoding();
                StreamWriter sw = new StreamWriter(xmlFile);
                sw.WriteLine("<?xml version="1.0" encoding="utf-8"?>");
                sw.WriteLine(utf.GetString(arr).Trim());
                sw.Flush();
                sw.Close();
            }
            catch (System.Exception ex)
            {
                throw ex;
            }
            finally
            {
                if (writer != null) writer.Close();
            }
        }

XML与DataSet的相互转换类 

送给大家一个XML与DataSet的相互转换的类:
XmlDatasetConvert 该类提供了四种方法：
1、将xml对象内容字符串转换为DataSet
2、将xml文件转换为DataSet
3、将DataSet转换为xml对象字符串
4、将DataSet转换为xml文件

XmlDatasetConvert.cs
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)
        {
            StringReader stream = null;
            XmlTextReader reader = null;
            try
            {
                XmlDocument xmld = new XmlDocument();
                xmld.Load(xmlFile);

                DataSet xmlDS = new DataSet();
                stream = new StringReader(xmld.InnerXml);
                //从stream装载到XmlTextReader
                reader = new XmlTextReader(stream);
                xmlDS.ReadXml(reader);
                //xmlDS.ReadXml(xmlFile);
                return xmlDS;
            }
            catch (System.Exception ex)
            {
                throw ex;
            }
            finally
            {
                if (reader != null) reader.Close();
            }
        }

        //将DataSet转换为xml对象字符串
        public static string ConvertDataSetToXML(DataSet xmlDS)
        {
            MemoryStream stream = null;
            XmlTextWriter writer = null;

            try
            {
                stream = new MemoryStream();
                //从stream装载到XmlTextReader
                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();
            }
            catch (System.Exception ex)
            {
                throw ex;
            }
            finally
            {
                if (writer != null) writer.Close();
            }
        }

        //将DataSet转换为xml文件
        public static void ConvertDataSetToXMLFile(DataSet xmlDS,string xmlFile)
        {
            MemoryStream stream = null;
            XmlTextWriter writer = null;

            try
            {
                stream = new MemoryStream();
                //从stream装载到XmlTextReader
                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);

                //返回Unicode编码的文本
                UnicodeEncoding utf = new UnicodeEncoding();
                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 )
            {
                throw ex;
            }
            finally
            {
                if (writer != null) writer.Close();
            }
        }

    }
}

使用示例
using System;
using System.Collections.Generic;
using System.Text;
using System.Xml;
using System.Data;

namespace XmlDesign
{
    class Program
    {
        static void Main(string[] args)
        {
            DataSet ds = new DataSet();

            转换一个XML文件(本地网络均可)为一个DataSet#region 转换一个XML文件(本地网络均可)为一个DataSet
            //http://news.baidu.com/n?cmd=1&class=sportnews&tn=rss
            //F:study01CSharp_Study02SourceXmlDesignXmlDesignSave_Plan.xml
            ds = XmlDatasetConvert.ConvertXMLFileToDataSet(@"http://news.baidu.com/n?cmd=1&class=sportnews&tn=rss");
            Console.WriteLine("数据集名为"{0}",包含{1}个表", ds.DataSetName, ds.Tables.Count);
            foreach(DataTable dt in ds.Tables)
            {
                PrintTableName(dt.TableName);
            };
            #endregion

            构造一个DataSet,并转换为XML字符串#region 构造一个DataSet,并转换为XML字符串
            DataSet ds1 = new DataSet();
            DataTable dt1 = new DataTable();
            dt1.TableName = "test";
            dt1.Columns.Add("id");
            dt1.Columns.Add("name");
            dt1.Rows.Add("i001", "hekui");
            dt1.Rows.Add("i002", "liyang");

            DataTable dt2 = new DataTable();
            dt2.TableName = "test1";
            dt2.Columns.Add("bookid");
            dt2.Columns.Add("bookname");
            dt2.Rows.Add("b001", "书本1");
            dt2.Rows.Add("b002", "书本2");

            ds1.Tables.Add(dt1);
            ds1.Tables.Add(dt2);
            ds1.DataSetName = "方案";
            string xmlOut = XmlDatasetConvert.ConvertDataSetToXML(ds1);
            #endregion

            转换一个XML字符串为一个DataSet#region 转换一个XML字符串为一个DataSet
            DataSet ds2 = new DataSet();
            ds2 = XmlDatasetConvert.ConvertXMLToDataSet(xmlOut);
            Console.WriteLine("数据集名为"{0}",包含{1}个表", ds2.DataSetName, ds2.Tables.Count);
            foreach (DataTable dt in ds2.Tables)
            {
                PrintTableName(dt.TableName);
            };
            #endregion

            转换一个Dataset为一个XML文件#region 转换一个Dataset为一个XML文件
            XmlDatasetConvert.ConvertDataSetToXMLFile(ds2, "c:\adadsda1.xml");
            #endregion
            
            Console.ReadLine();
        }

        private static void PrintTableName(string tableName)
        {
            Console.WriteLine(tableName);
        }
    }
}