Question

I have XML like:

<RES>
 <MUL>
  <SIN>
   <KEY name="a">
    <VALUE>a1</VALUE>
   </KEY>
   <KEY name="b">
    <VALUE>b1</VALUE>
   </KEY>
   <KEY name="c">
    <VALUE>c1</VALUE>
   </KEY>
   <KEY name="need">
    <MUL>
     <SIN>
      <KEY name="needID">
       <VALUE>ID</VALUE>
      </KEY>
      <KEY name="needOther">
       <VALUE>other</VALUE>
      </KEY>
      <KEY name="needOther2">
       <VALUE>other2</VALUE>
      </KEY>
     </SIN>
    </MUL>
   </KEY>
  </SIN>
 </MUL>
</RES>

My question is how to get value ‘id’ from the node with the name of needID ?

I tried with

XmlDocument xx = new XmlDocument();
xx.Load(MYDOC);

XmlNodeList node = xx.SelectNodes("/RES/MUL/SIN/KEY[@name='need']");

but after that I can’t pick needID with

XDocument doc = new XDocument(node);
var cource = from x in doc.Descendants("KEY")
select new { ID = doc.Element("VALUE").Value };

Please, help me!

Thanks! 🙂

Answer 1

You need something like this:

// you're expecting only a single node - right?? So use .SelectSingleNode!
XmlNode node = xx.SelectSingleNode("/RES/MUL/SIN/KEY[@name='need']");

// if we found the node...
if(node != null)
{
    // get "subnode" inside that node
    XmlNode valueNode = node.SelectSingleNode("MUL/SIN/KEY[@name='needID']/VALUE");

    // if we found the <MUL>/<SIN>/<KEY name='needID'>/<VALUE> subnode....
    if(valueNode != null)
    {
        // get the inner text = the text of the XML element...
        string value = valueNode.InnerText;
    }
}

or you could even combine that into a single XPath operation, assuming you know that you have at most one single matching node in your XML document:

// define XPath
string xpath = "/RES/MUL/SIN/KEY[@name='need']/MUL/SIN/KEY[@name='needID']/VALUE";

// you're expecting only a single node - right?? So use .SelectSingleNode!
XmlNode node = xx.SelectSingleNode(xpath);

// if we found the node...
if(node != null)
{
    // get the inner text = the text of the XML element...
    string value = node.InnerText;
}