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。