Xml搜索特定节点并添加子节点c＃

Question

Hi guys we are working on a project at the school but i am stuck and need you guys help.

i have an xml file with user data:

<Bruger>
  <Spejder>
    <Navn>Fatih</Navn>
    <Efternavn>Karaman</Efternavn>
    <Cpr>2</Cpr>
    <Cprno>2</Cprno>
    <Alder>12</Alder>
    <Kontakt>44</Kontakt>
  </Spejder>
  <Spejder>
    <Navn>Adel</Navn>
    <Efternavn>Karaman</Efternavn>
    <Cpr>1</Cpr>
    <Cprno>2</Cprno>
    <Alder>12</Alder>
    <Kontakt>44</Kontakt>
  </Spejder>
  <Spejder>
    <Navn>Max</Navn>
    <Efternavn>Karaman</Efternavn>
    <Cpr>3</Cpr>
    <Cprno>2</Cprno>
    <Alder>12</Alder>
    <Kontakt>44</Kontakt>
  </Spejder>
</Bruger>

when one user login to the application they should be able to join activities but when i program it and login with the last user no matter it makes a new child at the top of the xml.

here is the code:

{
    XmlDocument document = new XmlDocument();
    document.Load(@"Spejder.xml");
    {
         XmlNodeList xnList = document.SelectNodes("Bruger/Spejder");
         foreach (XmlNode xn in xnList)
         {
            string Navn = xn["Navn"].InnerText;
            if (label15.Text == Navn)
            {
                 XmlNode tilmeld = document.CreateElement("tilmeld");
                 tilmeld.InnerText = "new child";
                 XmlNode parentNode=document.SelectSingleNode("/Bruger/Spejder");
                 parentNode.InsertAfter(tilmeld, parentNode.LastChild);
                 document.Save(@"Spejder.xml");
            }
         }
     }
}

I really appreciate for incoming helps :)

Answer 1

string inputName = "Fatih";

        XDocument doc = XDocument.Load("Spejder.xml");

        foreach (var item in doc.Descendants("Spejder"))
        {
            var xElement = item.Element("Navn");
            if (xElement != null)
            {
                string currentName = xElement.Value;
                if (currentName == inputName)
                {

                    var newChildelement = new XElement("tilmeld", "new child");

                    var subs = item.Element("tilmeld");

                    if (subs != null)
                    {
                        subs.Add(newChildelement);
                    }
                    else
                    {
                        XNode node = new XElement("tilmeld", newChildelement);
                        item.Add(node);
                    }
                }
            }
        }
        doc.Save("Spejder.xml");

Answer 2

find user. if found then add a child element.

var user = document.SelectSingleNode("/Bruger/Spejder[Navn/text() = '" + label15.Text + "']")
if (null != user)
{
   var register = document.CreateElement("tilmeld");
   register.InnerText = "new child";
   user.AppendChild(register);
}