XPath 的简单应用（源代码）

using System;
using System.Collections.Generic;
using System.Text;
using System.Xml;
using System.Data;
using System.Xml.XPath;
using System.IO;
namespace TestXPath
...{
    class XMLOpretion
    ...{
        /**////<summary>
        /// recieve xml return DataTable, Static Method
        ///</summary>
        /// <param name="url"> the path of xml document
        /// </parm>
        public static DataTable FillDT(string url)
        ...{
            StreamReader sr = new StreamReader(url);
            XmlDataDocument xd = new XmlDataDocument();
            xd.DataSet.ReadXml(sr);
            DataTable dt=xd.DataSet.Tables[0];
            xd = null;
            sr.Close();
            return dt;
        }
        /**////<summary>
        /// recieve xml,the XPath , return XPathNodeIterator, Static Method
        ///</summary>
        /// <param name="url"> the path of xml document
        /// </parm>
        /// <param name="XPathSelect">the XPath select sentence</param>
        public static XPathNodeIterator XPathIter(string url, string XPathSelect)
        ...{
            StreamReader sr = new StreamReader(url);
            XPathDocument doc = new XPathDocument(sr);
            XPathNavigator myNav = doc.CreateNavigator();
            XPathNodeIterator myIter = myNav.Select(XPathSelect);
            doc = null;
            sr.Close();
            return myIter;
        }

    }
}