C#:xml操作（待补充）

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;
using System.Windows.Forms;

namespace MyCommanHelper
{
    public class XMLHelper
    {

    #region 读取节点值

        /// <summary>
        /// 读取节点值
        /// </summary>
        /// <param name="doc"></param>
        /// <param name="Section"></param>
        /// <param name="Key"></param>
        /// <returns></returns>
        public static string XmlReadValue(XmlDocument doc, string Section, string Key)
        {
            XmlNode result = doc.SelectSingleNode(Section);
            string ss = "";
            if (null != result)
            {
                ss = result.SelectSingleNode(Key).InnerText;
            }
            return ss;
        }

        /// <summary>
        /// 获取二层小结下的键值
        /// </summary>
        /// <param name="doc"></param>
        /// <param name="Section"></param>
        /// <param name="subSection"></param>
        /// <param name="Key"></param>
        /// <returns></returns>
        public static string XmlReadValue(XmlDocument doc, string Section, string subSection, string Key)
        {
            try
            {
                XmlNode result = doc.SelectSingleNode(Section);
                if (null != result)
                {
                    XmlNodeList childnodes = result.ChildNodes;
                    for (int i = 0; i < childnodes.Count; i++)
                    {
                        XmlNode node = childnodes[i];
                        if (node.LocalName.Equals(subSection))
                        {
                            return node.SelectSingleNode(Key).InnerText;
                        }
                    }
                }
                return "";
            }
            catch
            {
                return "";
            }
        }

        /// <summary>
        /// 获取三层小结下的键值
        /// </summary>
        /// <param name="doc"></param>
        /// <param name="Section"></param>
        /// <param name="subSection"></param>
        /// <param name="sub2Section"></param>
        /// <param name="Key"></param>
        /// <returns></returns>
        public static string XmlReadValue(XmlDocument doc, string Section, string subSection, string sub2Section, string Key)
        {
            try
            {
                XmlNode result = doc.SelectSingleNode(Section);
                if (null != result)
                {
                    XmlNodeList parentNodes = result.ChildNodes;
                    for (int i = 0; i < parentNodes.Count; i++)
                    {
                        XmlNode node = parentNodes[i];
                        if (node.LocalName.Equals(subSection))
                        {
                            XmlNodeList childNodes = node.ChildNodes;
                            for (int j = 0; j < childNodes.Count; j++)
                            {
                                XmlNode subNode = childNodes[j];
                                if (subNode.LocalName.Equals(sub2Section))
                                {
                                    return subNode.SelectSingleNode(Key).InnerText;
                                }
                            }
                        }
                    }
                }
                return "";
            }
            catch (Exception)
            {
                return "";
            }
        }

        /// <summary>
        /// 获取四层小结下的键值
        /// </summary>
        /// <param name="doc"></param>
        /// <param name="Section"></param>
        /// <param name="subSection"></param>
        /// <param name="sub2Section"></param>
        /// <param name="sub3Section"></param>
        /// <param name="Key"></param>
        /// <returns></returns>
        public static string XmlReadValue(XmlDocument doc, string Section, string subSection, string sub2Section, string sub3Section, string Key)
        {
            try
            {
                XmlNode result = doc.SelectSingleNode(Section);
                if (null != result)
                {
                    XmlNodeList childnodes = result.ChildNodes;
                    for (int i = 0; i < childnodes.Count; i++)
                    {
                        XmlNode node = childnodes[i];
                        if (node.LocalName.Equals(subSection))
                        {
                            XmlNodeList subNodeList = node.ChildNodes;
                            for (int j = 0; j < subNodeList.Count; j++)
                            {
                                XmlNode subNode = subNodeList[j];
                                if (subNode.LocalName.Equals(sub2Section))
                                {
                                    XmlNodeList sub2NodeList = subNode.ChildNodes;
                                    for (int k = 0; k < sub2NodeList.Count; k++)
                                    {
                                        XmlNode sub2Node = sub2NodeList[k];
                                        if (sub2Node.LocalName.Equals(sub3Section))
                                        {
                                            return sub2Node.SelectSingleNode(Key).InnerText;
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
                return "";
            }
            catch
            {
                return "";
            }
        }

    #endregion

    #region 写入节点值

        /// <summary>
        /// 写入节点值
        /// </summary>
        /// <param name="doc"></param>
        /// <param name="sXMLPath"></param>
        /// <param name="Section"></param>
        /// <param name="Key"></param>
        /// <param name="Value"></param>
        public static void XmlWriteValue(XmlDocument doc, string sXMLPath, string Section, string Key, string Value)
        {
            try
            {
                XmlNode result = doc.SelectSingleNode(Section);
                if (null == result)
                {
                    result = (XmlNode)doc.CreateElement(Section);
                    doc.AppendChild(result);

                    XmlNode subNode = doc.CreateElement(Key);
                    subNode.InnerText = Value;
                    result.AppendChild(subNode);
                }
                else
                {
                    XmlNode subNode = result.SelectSingleNode(Key);
                    if (null == subNode)
                    {
                        subNode = doc.CreateElement(Key);
                        subNode.InnerText = Value;
                        result.AppendChild(subNode);
                    }
                    else
                    {
                        subNode.InnerText = Value;
                    }
                }

                doc.Save(sXMLPath);
            }
            catch (System.Exception ex)
            {
                MessageBox.Show("写入节点值错误! " + ex.Message);
            }
        }

        public static void XmlWriteValue(XmlDocument doc, string sXMLPath, string Section, string subSection, string Key, string Value)
        {
            try
            {
                XmlNode result = doc.SelectSingleNode(Section);
                if (null == result)
                {
                    result = (XmlNode)doc.CreateElement(Section);
                    doc.AppendChild(result);

                    XmlElement subEle = doc.CreateElement(subSection);
                    result.AppendChild(subEle);

                    XmlElement sub2Ele = doc.CreateElement(Key);
                    sub2Ele.InnerText = Value;
                    subEle.AppendChild(sub2Ele);
                }
                else
                {
                    XmlNode subEle = result.SelectSingleNode(subSection);
                    if (null == subEle)
                    {
                        subEle = doc.CreateElement(subSection);
                        result.AppendChild(subEle);

                        XmlElement sub2Ele = doc.CreateElement(Key);
                        sub2Ele.InnerText = Value;
                        subEle.AppendChild(sub2Ele);
                    }
                    else
                    {
                        XmlNode sub2Ele = subEle.SelectSingleNode(Key);
                        if (null == sub2Ele)
                        {
                            sub2Ele = doc.CreateElement(Key);
                            sub2Ele.InnerText = Value;
                            subEle.AppendChild(sub2Ele);
                        }
                        else
                        {
                            sub2Ele.InnerText = Value;
                        }
                    }
                }
            }
            catch (System.Exception ex)
            {
                MessageBox.Show("写入节点值错误! " + ex.Message);
            }
        }

        public static void XmlWriteValue(XmlDocument doc, string sXMLPath, string Section, string subSection, string sub2Section, string Key, string Value)
        {
            try
            {
                XmlNode result = doc.SelectSingleNode(Section);
                if (null == result)
                {
                    result = (XmlNode)doc.CreateElement(Section);
                    doc.AppendChild(result);
                }
                XmlNode subEle = result.SelectSingleNode(subSection);
                if (null == subEle)
                {
                    subEle = doc.CreateElement(subSection);
                    result.AppendChild(subEle);
                }

                XmlNode sub2Ele = result.SelectSingleNode(sub2Section);
                if (null == sub2Ele)
                {
                    sub2Ele = doc.CreateElement(sub2Section);
                    subEle.AppendChild(sub2Ele);
                }

                XmlNode sub3Ele = subEle.SelectSingleNode(Key);
                if (null == sub3Ele)
                {
                    sub3Ele = doc.CreateElement(Key);
                    sub3Ele.InnerText = Value;
                    sub2Ele.AppendChild(sub2Ele);
                }
                else
                {
                    sub3Ele.InnerText = Value;
                }

                doc.Save(sXMLPath);
            }
            catch (System.Exception ex)
            {
                MessageBox.Show("写入节点值错误! " + ex.Message);
            }
        }

        public static void XmlWriteValue(XmlDocument doc, string sXMLPath,string Section, string subSection, string sub2Section,string sub3Section, string Key, string Value)
        {

            try
            {
                XmlNode result = doc.SelectSingleNode(Section);
                if (null == result)
                {
                    result = (XmlNode)doc.CreateElement(Section);
                    doc.AppendChild(result);
                }
                XmlNode subEle = result.SelectSingleNode(subSection);
                if (null == subEle)
                {
                    subEle = doc.CreateElement(subSection);
                    result.AppendChild(subEle);
                }

                XmlNode sub2Ele = result.SelectSingleNode(sub2Section);
                if (null == sub2Ele)
                {
                    sub2Ele = doc.CreateElement(sub2Section);
                    subEle.AppendChild(sub2Ele);
                }

                XmlNode sub3Ele = result.SelectSingleNode(sub3Section);
                if (null == sub2Ele)
                {
                    sub3Ele = doc.CreateElement(sub3Section);
                    sub2Ele.AppendChild(sub3Ele);
                }

                XmlNode sub4Ele = subEle.SelectSingleNode(Key);
                if (null == sub3Ele)
                {
                    sub4Ele = doc.CreateElement(Key);
                    sub4Ele.InnerText = Value;
                    sub3Ele.AppendChild(sub2Ele);
                }
                else
                {
                    sub4Ele.InnerText = Value;
                }

                doc.Save(sXMLPath);
            }
            catch (System.Exception ex)
            {
                MessageBox.Show("写入节点值错误! " + ex.Message);
            }
        }

    #endregion

    #region 修改节点值

        /// <summary>
        /// 修改节点值
        /// </summary>
        /// <param name="doc"></param>
        /// <param name="sXMLPath"></param>
        /// <param name="Section"></param>
        /// <param name="Key"></param>
        /// <param name="Value"></param>
        public static void XmlEditValue(XmlDocument doc, string sXMLPath, string Section, string Key, string Value)
        {
            XmlNode result = doc.SelectSingleNode(Section);
            if (null != result)
            {
                if (Value == "")
                {
                    result.SelectSingleNode(Key).InnerText = "无";
                }
                else
                {
                    result.SelectSingleNode(Key).InnerText = Value;
                }
            }
            doc.Save(sXMLPath);
        }

        public static void XmlEditValue(XmlDocument doc, string sXMLPath, string Section, string sValue1, string Key, string Value)
        {
            XmlNode result = doc.SelectSingleNode(Section);
            if (null != result)
            {
                XmlNodeList childnodes = result.ChildNodes;
                for (int i = 0; i < childnodes.Count; i++)
                {
                    XmlNode node = childnodes[i];
                    if (node.LocalName.Equals(sValue1))
                    {
                        if (Value == "")
                        {
                            node.SelectSingleNode(Key).InnerText = "无";
                        }
                        else
                        {
                            node.SelectSingleNode(Key).InnerText = Value;
                        }
                    }
                }
            }
            doc.Save(sXMLPath);
        }

        public static void XmlEditValue(XmlDocument doc, string sXMLPath,
            string Section, string sValue1,
            string sValue2, string Key, string Value)
        {
            XmlNode result = doc.SelectSingleNode(Section);
            if (null != result)
            {
                XmlNodeList parentNodes = result.ChildNodes;
                for (int ii = 0; ii < parentNodes.Count; ii++)
                {
                    XmlNode node = parentNodes[ii];
                    if (node.LocalName.Equals(sValue1))
                    {
                        XmlNodeList childNodes = node.ChildNodes;
                        for (int i = 0; i < childNodes.Count; i++)
                        {
                            XmlNode node2 = childNodes[i];
                            if (node2.LocalName.Equals(sValue2))
                            {
                                if (Value == "")
                                {
                                    node2.SelectSingleNode(Key).InnerText = "无";
                                }
                                else
                                {
                                    node2.SelectSingleNode(Key).InnerText = Value;
                                }
                            }
                        }
                    }
                }
            }
            doc.Save(sXMLPath);
        }

        public static void XmlEditValue(XmlDocument doc, string sXMLPath,
            string Section, string sValue1, string sValue2,
            string sValue3, string Key, string Value)
        {
            XmlNode node = doc.SelectSingleNode(Section);
            if (null != node)
            {
                XmlNodeList childNodes = node.ChildNodes;
                for (int i = 0; i < childNodes.Count; i++)
                {
                    XmlNode node2 = childNodes[i];
                    if (node2.LocalName.Equals(sValue1))
                    {
                        XmlNodeList list2 = node2.ChildNodes;
                        for (int j = 0; j < list2.Count; j++)
                        {
                            XmlNode node3 = list2[j];
                            if (node3.LocalName.Equals(sValue2))
                            {
                                XmlNodeList list3 = node3.ChildNodes;
                                for (int k = 0; k < list3.Count; k++)
                                {
                                    XmlNode node4 = list3[k];
                                    if (node4.LocalName.Equals(sValue3))
                                    {
                                        if (Value == "")
                                        {
                                            node4.SelectSingleNode(Key).InnerText = "无";
                                        }
                                        else
                                        {
                                            node4.SelectSingleNode(Key).InnerText = Value;
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }
            doc.Save(sXMLPath);
        }
    #endregion 

    }
}

 public void createXml(double meters)
        {
            XmlDocument xml = new XmlDocument();
            //xml文件的相对路径
            string stringPath = Application.ExecutablePath.Substring(0, Application.ExecutablePath.LastIndexOf('\\')) + "\\searchStation.xml";
            if (!System.IO.File.Exists(stringPath))
            {
                System.IO.FileStream fileStream = new System.IO.FileStream(stringPath, System.IO.FileMode.Create, System.IO.FileAccess.ReadWrite, System.IO.FileShare.ReadWrite);
                fileStream.Close();
                System.IO.File.WriteAllText(stringPath, "<?xml version=\"1.0\"?><ROOT><AREA>"+meters.ToString()+"</AREA></ROOT>");
            }
            xml.Load(stringPath);
            XmlNode nodes = xml.DocumentElement;
            foreach (XmlNode item in nodes.ChildNodes)
            {
                if (item.Name == "AREA")
                {
                    item.InnerText = meters.ToString();
                }
            }
            xml.Save(stringPath);
        }

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