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c#xmllinq-to-xmlxmlnodexmlnodelist

Loop through multiple subnodes in XML


  <Sections>
    <Classes>
      <Class>VI</Class>
      <Class>VII</Class>
    </Classes>
    <Students>
      <Student>abc</Student>
      <Student>def</Student>
    </Students>    
  </Sections>

I have to loop through Classes to get 'Class' into an array of strings. I have to also loop through 'Students' to get 'Student' put into an array of strings.

XDocument doc.Load("File.xml");
     string str1;
     foreach(XElement mainLoop in doc.Descendants("Sections")) 
       {   
          foreach(XElement classLoop in mainLoop.Descendants("Classes"))
                str1 = classLoop.Element("Class").Value +",";
       //Also get Student value
        }

is not working to get all the classes. Also, I need to rewrite this without using LINQ to XML, i.e using XmlNodeList and XmlNodes.

XmlDocument doc1 = new XmlDocument();
doc1.Load("File.xml");
foreach(XmlNode mainLoop in doc.SelectNodes("Sections")) ??

Not sure how to go about it.


Solution

  • The XPath is straightforward. To get the results into an array you can either use LINQ or a regular loop.

    var classNodes = doc.SelectNodes("/Sections/Classes/Class");
    // LINQ approach
    string[] classes = classNodes.Cast<XmlNode>()
                                 .Select(n => n.InnerText)
                                 .ToArray();
    
    var studentNodes = doc.SelectNodes("/Sections/Students/Student");
    // traditional approach
    string[] students = new string[studentNodes.Count];
    for (int i = 0; i < studentNodes.Count; i++)
    {
        students[i] = studentNodes[i].InnerText;
    }