Personal summary of reading and writing all xml nodes and data summary of reading xml nodes

Read:

 //打开某文件(假设web.config在根目录中)
    string filename=Server.MapPath("/") + @"Webapplication1\web.config";
    xmlDocument xmldoc= new XmlDocument();
    xmldoc.Load(filename);
 
    //得到顶层节点列表
    XmlNodeList topM=xmldoc.DocumentElement.ChildNodes;
    foreach(XmlElement element in topM)
    {
     if(element.Name.ToLower()=="appsettings")
     {
 
      //得到该节点的子节点
      XmlNodeList nodelist=element.ChildNodes;
 
      if ( nodelist.Count >0 )
      {
       //DropDownList1.Items.Clear();
 
       foreach(XmlElement el in nodelist)//读元素值
       {
        //DropDownList1.Items.Add(el.Attributes["key"].InnerXml);
        //this.TextBox2.Text=el.Attributes["key"].InnerText;
        this.TextBox2.Text=el.Attributes["key"].Value;
        this.Label1.Text=el.Attributes["value"].Value;
 
 
            //同样在这里可以修改元素值,在后面save。
         //  el.Attributes["value"].Value=this.TextBox2.Text;
       }
 
      }
     }
    }

xmldoc.Save(filename);

Add an element under a node and set the value:

 if(element.Name.ToLower()=="appsettings")
    {
 
     XmlElement elem =xmldoc.CreateElement("add");
     
     element.AppendChild(elem);
     elem.InnerText="ltp";
 
     xmldoc.Save(filename);
       
    }

Effect:

<appSettings>
    <add key="密码" value="admin" />
    <add>ltp</add>
  </appSettings>

Add an element under a certain node and add two attributes:

 if(element.Name.ToLower()=="appsettings")
    {
 
     XmlElement elem =xmldoc.CreateElement("add");
     element.AppendChild(elem);
 
     XmlAttribute xa=xmldoc.CreateAttribute("key");
     xa.Value="ltp";
 
     XmlAttribute xa2=xmldoc.CreateAttribute("value");
     xa2.Value="first";
 
     elem.SetAttributeNode(xa);
     elem.SetAttributeNode(xa2);
 
     xmldoc.Save(filename);
       
    }

Effect:

  <appSettings>
    <add key="密码" value="admin" />
    <add key="ltp" value="first" />
  </appSettings>
 
//添加空元素：
   XmlNode node=doc.CreateElement(groupname);
     node.InnerText="";
     doc.LastChild.AppendChild(node);
 
     doc.Save(xmlfile);

Delete a node element

string itemname=this.listBox1.SelectedItem.ToString();
   
   this.listBox1.Items.Remove(this.listBox1.SelectedItem);
 
   //begin del xmlfile
   XmlDocument doc=new XmlDocument();
   doc.Load(xmlfile);
   
   XmlNodeList topM=doc.DocumentElement.ChildNodes;
   foreach(XmlElement element in topM)
   {
    if(element.Name==this.comboBox1.Text)
    {
 
     //得到该节点的子节点
     XmlNodeList nodelist=element.ChildNodes;      
 
     foreach(XmlElement el in nodelist)//读元素值
     {       
      if(el.Attributes["key"].Value==itemname)
      {
       element.RemoveChild(el);
      }
 
     }//循环元素
      
    }//得到组
 
   }//循环组
   doc.Save(xmlfile);  //一定要保存一下，否则不起作用
 
//筛选数据
PRivate void Reader_Xml(string pathFlie)
{
   XmlDocument Xmldoc=new XmlDocument();
   Xmldoc.Load(pathFlie);
   XmlNodeList Record1=Xmldoc.DocumentElement.SelectNodes(Code[@id='1'])
   int f=0;
   foreach(XmlNode xnode in Record1)
    {
 
    }
} /**//*读取xml数据   两种xml方式*/
<aaa>
     <bb>something</bb>
     <cc>something</cc>
</aaa>
 
<aaa>
    <add key="123" value="321"/>
</aaa>
/**//*第一种方法*/
DS.ReadXml("your xmlfile name");
Container.DataItem("bb");
Container.DataItem("cc");
DS.ReadXmlSchema("your xmlfile name");
 
/**//*第二种方法*/
<aaa>
    <add key="123" value="321"/>
</aaa>

If I want to find 123 then How should I write when I get 321?

using System.XML;
XmlDataDocument xmlDoc = new System.Xml.XmlDataDocument();
xmlDoc.Load(@"c:\Config.xml");
XmlElement elem = xmlDoc.GetElementById("add");
string str = elem.Attributes["value"].Value
 
 
/**//*第三种方法:  SelectSingleNode  读取两种格式的xml *---/
--------------------------------------------------------------------
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <appSettings>
       <ConnectionString>Data Source=yf; user id=ctm_dbo;passWord=123</ConnectionString>             
  </appSettings>
</configuration>
--------------------------------------------------------------------------
XmlDocument doc = new XmlDocument();
doc.Load(strXmlName);
 
    XmlNode node=doc.SelectSingleNode("/configuration/appSettings/ConnectionString");
    if(node!=null)
    {
     string k1=node.Value;    //null
     string k2=node.InnerText;//Data Source=yf; user id=ctm_dbo;password=123
     string k3=node.InnerXml;//Data Source=yf; user id=ctm_dbo;password=123
     node=null;
    }
 
********************************************************************
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <appSettings>
       <add key="ConnectionString" value="Data Source=yf; user id=ctm_dbo;password=123" />             
  </appSettings>
</configuration>
**--------------------------------------------------------------------**
     XmlNode node=doc.SelectSingleNode("/configuration/appSettings/add");
    if(node!=null)
    {
     string k=node.Attributes["key"].Value;
     string v=node.Attributes["value"].Value;
     node=null;
    }
*--------------------------------------------------------------------*
    XmlNode node=doc.SelectSingleNode("/configuration/appSettings/add");
    if(node!=null)
    {
     XmlNodeReader nr=new XmlNodeReader(node);
     nr.MoveToContent();
    //检查当前节点是否是内容节点。如果此节点不是内容节点，则读取器向前跳至下一个内容节点或文件结尾。
     nr.MoveToAttribute("value");
     string s=nr.Value;
     node=null;
    }

The above is the personal summary of reading and writing all nodes in xml and the summary of data in reading xml nodes. For more related content, please pay attention to the PHP Chinese website (www.php.cn)!