C#操作XML通用方法汇总

在.net的项目开发中，经常会对XML文件进行操作，由于XML文件可以实现跨平台传输，较多的应用在数据传输中，特总结以下几种常用的XML操作方法：

1.创建XML文档：

  /// <summary>
  /// 创建XML文档
  /// </summary>
  /// <param name="name">根节点名称</param>
  /// <param name="type">根节点的一个属性值</param>
  /// <returns>XmlDocument对象</returns>
  public static XmlDocument CreateXmlDocument(string name, string type)
  {
   XmlDocument doc;
   try
   {
    doc = new XmlDocument();
    doc.LoadXml("<" + name + "/>");
    var rootEle = doc.DocumentElement;
    rootEle?.SetAttribute("type", type);
   }
   catch (Exception er)
   {
    throw new Exception(er.ToString());
   }
   return doc;
  }

2.读取XML文档中的数据：

  /// <summary>
  /// 读取数据
  /// </summary>
  /// <param name="path">路径</param>
  /// <param name="node">节点</param>
  /// <param name="attribute">属性名，非空时返回该属性值，否则返回串联值</param>
  /// <returns>string</returns>
  public static string Read(string path, string node, string attribute)
  {
   var value = "";
   try
   {
    var doc = new XmlDocument();
    doc.Load(path);
    var xn = doc.SelectSingleNode(node);
    if (xn != null && xn.Attributes != null)
     value = (attribute.Equals("") ? xn.InnerText : xn.Attributes[attribute].Value);
   }
   catch (Exception er)
   {
    throw new Exception(er.ToString());
   }
   return value;
  }

3.对XML文档插入数据：

  /// <summary>
  /// 插入数据
  /// </summary>
  /// <param name="path">路径</param>
  /// <param name="node">节点</param>
  /// <param name="element">元素名，非空时插入新元素，否则在该元素中插入属性</param>
  /// <param name="attribute">属性名，非空时插入该元素属性值，否则插入元素值</param>
  /// <param name="value">值</param>
  /// <returns></returns>
  public static void Insert(string path, string node, string element, string attribute, string value)
  {
   try
   {
    var doc = new XmlDocument();
    doc.Load(path);
    var xn = doc.SelectSingleNode(node);
    if (element.Equals(""))
    {
     if (!attribute.Equals(""))
     {
      var xe = (XmlElement)xn;
      xe?.SetAttribute(attribute, value);
      //xe?.SetAttribute(attribute, value);
     }
    }
    else
    {
     var xe = doc.CreateElement(element);
     if (attribute.Equals(""))
      xe.InnerText = value;
     else
      xe.SetAttribute(attribute, value);
     xn?.AppendChild(xe);
    }
    doc.Save(path);
   }
   catch (Exception er)
   {
    throw new Exception(er.ToString());
   }
  }

4.修改XML文档中的数据：

  /// <summary>
  /// 修改数据
  /// </summary>
  /// <param name="path">路径</param>
  /// <param name="node">节点</param>
  /// <param name="attribute">属性名，非空时修改该节点属性值，否则修改节点值</param>
  /// <param name="value">值</param>
  /// <returns></returns>
  public static void Update(string path, string node, string attribute, string value)
  {
   try
   {
    var doc = new XmlDocument();
    doc.Load(path);
    var xn = doc.SelectSingleNode(node);
    var xe = (XmlElement)xn;
    if (attribute.Equals(""))
    {
     if (xe != null) xe.InnerText = value;
    }
    else
    {
     xe?.SetAttribute(attribute, value);
    }
    doc.Save(path);
   }
   catch (Exception er)
   {
    throw new Exception(er.ToString());
   }
  }

5.删除XML文档中数据：

  /// <summary>
  /// 删除数据
  /// </summary>
  /// <param name="path">路径</param>
  /// <param name="node">节点</param>
  /// <param name="attribute">属性名，非空时删除该节点属性值，否则删除节点值</param>
  /// <returns></returns>
  public static void Delete(string path, string node, string attribute)
  {
   try
   {
    var doc = new XmlDocument();
    doc.Load(path);
    var xn = doc.SelectSingleNode(node);
    var xe = (XmlElement)xn;
    if (attribute.Equals(""))
    {
     xn?.ParentNode?.RemoveChild(xn);
    }
    else
    {
     xe?.RemoveAttribute(attribute);
    }
    doc.Save(path);
   }
   catch (Exception er)
   {
    throw new Exception(er.ToString());
   }
  }

6.读取XML文档中指定节点数据：

  /// <summary>
  /// 获得xml文件中指定节点的节点数据
  /// </summary>
  /// <param name="path"></param>
  /// <param name="nodeName"></param>
  /// <returns></returns>
  public static string GetNodeInfoByNodeName(string path, string nodeName)
  {
   var xmlString = string.Empty;
   try
   {
    var xml = new XmlDocument();
    xml.Load(path);
    var root = xml.DocumentElement;
    if (root == null) return xmlString;
    var node = root.SelectSingleNode("//" + nodeName);
    if (node != null)
    {
     xmlString = node.InnerText;
    }
   }
   catch (Exception er)
   {
    throw new Exception(er.ToString());
   }
   return xmlString;
  }

7.获取XML指定节点的属性：

  /// <summary>
  /// 功能:读取指定节点的指定属性值
  /// </summary>
  /// <param name="path"></param>
  /// <param name="strNode">节点名称</param>
  /// <param name="strAttribute">此节点的属性</param>
  /// <returns></returns>
  public string GetXmlNodeAttributeValue(string path, string strNode, string strAttribute)
  {
   var strReturn = "";
   try
   {
    var xml = new XmlDocument();
    xml.Load(path);
    //根据指定路径获取节点
    var xmlNode = xml.SelectSingleNode(strNode);
    if (xmlNode != null)
    {
     //获取节点的属性，并循环取出需要的属性值
     var xmlAttr = xmlNode.Attributes;
     if (xmlAttr == null) return strReturn;
     for (var i = 0; i < xmlAttr.Count; i++)
     {
      if (xmlAttr.Item(i).Name != strAttribute) continue;
      strReturn = xmlAttr.Item(i).Value;
      break;
     }
    }
   }
   catch (XmlException xmle)
   {
    throw new Exception(xmle.Message);
   }
   return strReturn;
  }

8.设置XML文档中指定节点的属性：

 /// <summary>
  /// 功能:设置节点的属性值
  /// </summary>
  /// <param name="path"></param>
  /// <param name="xmlNodePath">节点名称</param>
  /// <param name="xmlNodeAttribute">属性名称</param>
  /// <param name="xmlNodeAttributeValue">属性值</param>
  public void SetXmlNodeAttributeValue(string path, string xmlNodePath, string xmlNodeAttribute, string xmlNodeAttributeValue)
  {
   try
   {
    var xml = new XmlDocument();
    xml.Load(path);
    //可以批量为符合条件的节点的属性付值
    var xmlNode = xml.SelectNodes(xmlNodePath);
    if (xmlNode == null) return;
    foreach (var xmlAttr in from XmlNode xn in xmlNode select xn.Attributes)
    {
     if (xmlAttr == null) return;
     for (var i = 0; i < xmlAttr.Count; i++)
     {
      if (xmlAttr.Item(i).Name != xmlNodeAttribute) continue;
      xmlAttr.Item(i).Value = xmlNodeAttributeValue;
      break;
     }
    }

   }
   catch (XmlException xmle)
   {
    throw new Exception(xmle.Message);
   }
  }

9.读取XML文档指定节点的值：

  /// <summary>
  /// 读取XML资源中的指定节点内容
  /// </summary>
  /// <param name="source">XML资源</param>
  /// <param name="xmlType">XML资源类型：文件，字符串</param>
  /// <param name="nodeName">节点名称</param>
  /// <returns>节点内容</returns>
  public static object GetNodeValue(string source, XmlType xmlType, string nodeName)
  {
   var xd = new XmlDocument();
   if (xmlType == XmlType.File)
   {
    xd.Load(source);
   }
   else
   {
    xd.LoadXml(source);
   }
   var xe = xd.DocumentElement;
   XmlNode xn = null;
   if (xe != null)
   {
     xn= xe.SelectSingleNode("//" + nodeName);

   }
   return xn.InnerText;
  }

10.更新XML文档指定节点的内容：

  /// <summary>
  /// 更新XML文件中的指定节点内容
  /// </summary>
  /// <param name="filePath">文件路径</param>
  /// <param name="nodeName">节点名称</param>
  /// <param name="nodeValue">更新内容</param>
  /// <returns>更新是否成功</returns>
  public static bool UpdateNode(string filePath, string nodeName, string nodeValue)
  {
   try
   {
    bool flag;
    var xd = new XmlDocument();
    xd.Load(filePath);
    var xe = xd.DocumentElement;
    if (xe == null) return false;
    var xn = xe.SelectSingleNode("//" + nodeName);
    if (xn != null)
    {
     xn.InnerText = nodeValue;
     flag = true;
    }
    else
    {
     flag = false;
    }
    return flag;
   }
   catch (Exception ex)
   {
    throw new Exception(ex.Message);
   }

  }
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11.将对象转化为XML文件，并存入指定目录：

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  /// <summary>
  /// 将对象转化为xml，并写入指定路径的xml文件中
  /// </summary>
  /// <typeparam name="T">C#对象名</typeparam>
  /// <param name="item">对象实例</param>
  /// <param name="path">路径</param>
  /// <param name="jjdbh">标号</param>
  /// <param name="ends">结束符号（整个xml的路径类似如下：C:\xmltest\201111send.xml，其中path=C:\xmltest,jjdbh=201111,ends=send）</param>
  /// <returns></returns>
  public static string WriteXml<T>(T item, string path, string jjdbh, string ends)
  {
   if (string.IsNullOrEmpty(ends))
   {
    //默认为发送
    ends = "send";
   }
   //控制写入文件的次数
   var i = 0;
   //获取当前对象的类型，也可以使用反射typeof(对象名)
   var serializer = new XmlSerializer(item.GetType());
   //xml的路径组合
   object[] obj = { path, "\\", jjdbh, ends, ".xml" };
   var xmlPath = string.Concat(obj);
   while (true)
   {
    try
    {
     //用filestream方式创建文件不会出现“文件正在占用中，用File.create”则不行
     var fs = System.IO.File.Create(xmlPath);
     fs.Close();
     TextWriter writer = new StreamWriter(xmlPath, false, Encoding.UTF8);
     var xml = new XmlSerializerNamespaces();
     xml.Add(string.Empty, string.Empty);
     serializer.Serialize(writer, item, xml);
     writer.Flush();
     writer.Close();
     break;
    }
    catch (Exception)
    {
     if (i < 5)
     {
      i++;
      continue;
     }
     break;
    }
   }
   return SerializeToXmlStr<T>(item, true);
  }

12.向一个已经存在的父节点中插入一个子节点：

  /// <summary>
  /// 向一个已经存在的父节点中插入一个子节点
  /// </summary>
  /// <param name="path"></param>
  /// <param name="parentNodePath">父节点</param>
  /// <param name="childnodename">子节点名称</param>
  public void AddChildNode(string path, string parentNodePath, string childnodename)
  {
   try
   {
    var xml = new XmlDocument();
    xml.Load(path);
    var parentXmlNode = xml.SelectSingleNode(parentNodePath);
    XmlNode childXmlNode = xml.CreateElement(childnodename);
    if ((parentXmlNode) != null)
    {
     //如果此节点存在
     parentXmlNode.AppendChild(childXmlNode);
    }
    else
    {
     //如果不存在就放父节点添加
     GetXmlRoot(path).AppendChild(childXmlNode);
    }

   }
   catch (XmlException xmle)
   {
    throw new Exception(xmle.Message);
   }
  }

以上的方法总结采用.net4.5版本和c#6.0语法，希望对大家的学习有所帮助，也希望大家多多支持我们。