XML与DataSet相互转换，DataSet查询

string hotspotXmlStr = string.Empty;
try
{
Stream fileStream = new FileStream(context.Server.MapPath("../data/Hotspot.xml"), FileMode.Open, FileAccess.Read, FileShare.Read);
StreamReader streamReader = new StreamReader(fileStream, Encoding.UTF8);
hotspotXmlStr = streamReader.ReadToEnd();
streamReader.Dispose();
}
catch (Exception ex)
{
logger.Error("读取XML文件Hotspot.xml出现异常！");
logger.Error("异常描述：\t" + ex.Message);
logger.Error("引发异常的方法：\t" + ex.TargetSite);
logger.Error("异常堆栈：\t" + ex.StackTrace);
}

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();
}
}

}