using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
 
using System.Xml;
 
namespace System
{
 
 
    /// <summary>
    /// XMLHelper XML文档操作管理器
    /// </summary>
    public class XMLHelper
    {
        public XMLHelper()
        {
            //
            // TODO: 在此处添加构造函数逻辑
            //
        }
 
 
        #region XML文档节点查询和读取
        /// <summary>
        /// 选择匹配XPath表达式的第一个节点XmlNode.
        /// </summary>
        /// <param name="xmlFileName">XML文档完全文件名(包含物理路径)</param>
        /// <param name="xpath">要匹配的XPath表达式(例如:"//节点名//子节点名")</param>
        /// <returns>返回XmlNode</returns>
        public static XmlNode GetXmlNodeByXpath(string xmlFileName, string xpath)
        {
            XmlDocument xmlDoc = new XmlDocument();
            try
            {
                xmlDoc.Load(xmlFileName); //加载XML文档
                XmlNode xmlNode = xmlDoc.SelectSingleNode(xpath);
                return xmlNode;
            }
            catch (Exception ex)
            {
                return null;
                //throw ex; //这里可以定义你自己的异常处理
            }
        }
 
        /// <summary>
        /// 选择匹配XPath表达式的节点列表XmlNodeList.
        /// </summary>
        /// <param name="xmlFileName">XML文档完全文件名(包含物理路径)</param>
        /// <param name="xpath">要匹配的XPath表达式(例如:"//节点名//子节点名")</param>
        /// <returns>返回XmlNodeList</returns>
        public static XmlNodeList GetXmlNodeListByXpath(string xmlFileName, string xpath)
        {
            XmlDocument xmlDoc = new XmlDocument();
 
            try
            {
                xmlDoc.Load(xmlFileName); //加载XML文档
                XmlNodeList xmlNodeList = xmlDoc.SelectNodes(xpath);
                return xmlNodeList;
            }
            catch (Exception ex)
            {
                return null;
                //throw ex; //这里可以定义你自己的异常处理
            }
        }
 
        /// <summary>
        /// 选择匹配XPath表达式的第一个节点的匹配xmlAttributeName的属性XmlAttribute.
        /// </summary>
        /// <param name="xmlFileName">XML文档完全文件名(包含物理路径)</param>
        /// <param name="xpath">要匹配的XPath表达式(例如:"//节点名//子节点名</param>
        /// <param name="xmlAttributeName">要匹配xmlAttributeName的属性名称</param>
        /// <returns>返回xmlAttributeName</returns>
        public static XmlAttribute GetXmlAttribute(string xmlFileName, string xpath, string xmlAttributeName)
        {
            string content = string.Empty;
            XmlDocument xmlDoc = new XmlDocument();
            XmlAttribute xmlAttribute = null;
            try
            {
                xmlDoc.Load(xmlFileName); //加载XML文档
                XmlNode xmlNode = xmlDoc.SelectSingleNode(xpath);
                if (xmlNode != null)
                {
                    if (xmlNode.Attributes.Count > 0)
                    {
                        xmlAttribute = xmlNode.Attributes[xmlAttributeName];
                    }
                }
            }
            catch (Exception ex)
            {
                throw ex; //这里可以定义你自己的异常处理
            }
            return xmlAttribute;
        }
        #endregion
 
        #region XML文档创建和节点或属性的添加、修改
        /// <summary>
        /// 创建一个XML文档
        /// </summary>
        ///