Question

I have a class that defines the xml and another class that defines the candidate and another class that it is a list of the class candidate.

I am trying to create dynamically the list according to number of nodes that I have in the xml.

I have tried all kind of variations and nothing worked, until the nodes Candidates I got all the information but the CandidateList came null all the time.

public class Candidate
{
}

public class CandidateList : List<Candidate>
{
}

public class Request
{
    public CandidateList CandidateList { get; set; }
}

<?xml version="1.0" encoding="utf-8"?>
<Requests>
  <Request>
    <MidaClientID>1040</MidaClientID>
    <!--elided other elements-->
    <OrderDescription></OrderDescription>
    <Candidates>
      <Candidate>
        <QuestNum>6</QuestNum>
        <!--elided other elements-->
        <EventNum>012</EventNum>
      </Candidate>
      <Candidate>
        <QuestNum>6</QuestNum>
         <!--elided other elements-->
        <EventNum>012</EventNum>
      </Candidate>
    </Candidates>
  </Request>
</Requests>

try
{
    IEnumerable<Request> req = from r in input.Descendants("Request")
    select new Request()
    {
        MidaClientID = (int)r.Element("MidaClientID") != 0 ? (int)r.Element("MidaClientID") : 0,
        Password = (string)r.Element("MidaClientPassword") != null ? (string)r.Element("MidaClientPassword") : string.Empty,
        ClientNum = (int)r.Element("ClientNum") != 0 ? (int)r.Element("ClientNum") : 0,
        ClientName = (string)r.Element("ClientName") != null ? (string)r.Element("ClientName") : string.Empty,
        ContactNum = (int)r.Element("ContactNum") != 0 ? (int)r.Element("ContactNum") : 0,
        ContactFirstName = (string)r.Element("ContactFirstName") != null ? (string)r.Element("ContactFirstName") : string.Empty,
        ContactLastName = (string)r.Element("ContactLastName") != null ? (string)r.Element("ContactLastName") : string.Empty,
        ContactEmail = (string)r.Element("ContactEmail") != null ? (string)r.Element("ContactEmail") : "",
        OrderID = (int)r.Element("OrderID") != 0 ? (int)r.Element("OrderID") : 0,
        OrderDesc = (string)r.Element("OrderDescription") != null ? (string)r.Element("OrderDescription") : "",
        CandidateList = (from i in input.Root.Element("Candidates").Elements("Candidate")
            select new Candidate()
            {
                QuestNum = (int)r.Element("QuestNum") != 0 ? (int)r.Element("QuestNum") : 0,
                CandNum = (int)r.Element("CandNum") != 0 ? (int)r.Element("CandNum") : 0,
                EventNum = (int)r.Element("EventNum") != 0 ? (int)r.Element("EventNum") : 0,
                EventDate = (string)(r.Element("EventDate")) == string.Empty ?
                            DateTime.Today : (DateTime)(r.Element("EventDate")),
                EventTime = (string)(r.Element("EventTime")) == string.Empty ?
                            DateTime.Now : (DateTime)(r.Element("EventTime")),
                CandFirstName = (string)r.Element("CandFirstName") != null ? (string)r.Element("CandFirstName") : string.Empty,
                CandLastName = (string)r.Element("CandLastName") != null ? (string)r.Element("CandLastName") : string.Empty,
                CandPhone1 = (string)r.Element("CandPhone1") != null ? (string)r.Element("CandPhone1") : string.Empty,
                CandPhone2 = (string)r.Element("CandPhone2") != null ? (string)r.Element("CandPhone2") : string.Empty,
                CandPhone3 = (string)r.Element("CandPhone3") != null ? (string)r.Element("CandPhone3") : string.Empty,
                CandAttach1 = (string)r.Element("CandAttach1") != null ? (string)r.Element("CandAttach1") : string.Empty,
                CandAttach2 = (string)r.Element("CandAttach2") != null ? (string)r.Element("CandAttach2") : string.Empty,
                CandAttach3 = (string)r.Element("CandAttach3") != null ? (string)r.Element("CandAttach3") : string.Empty
            }) as CandidateList
    };
    return req.ToList();
}

catch (Exception ex)
{
    throw ex;
}

Answer 1

Thanks for tidying up the question – having to scroll horizontally is a bit of a nightmare (will edit to show).

Anyway – it seems that your primary problem is the bit where you select your Candidates node:

CandidateList = (from i in input.Root.Element("Candidates").Elements("Candidate") 

The problem being that the linq query does not produce a CandidateList instance. One way to do that will be to add a range constructor to your CandidateList type and feed the linq query to it. Also – I think the input.Root is wrong.

public class CandidateList : List<Candidate>{
  public CandidateList() {}
  public CandidateList(IEnumerable<Candidate> range) : base(range) {}
}

//.. in 'new Request{' block
select new Candidate {
  // ... other members elided
  CandidateList = new CandidateList(
    (from i in r.Element("Candidates").Elements("Candidate") 
    select new Candidate()     
    {   
      //...all the Candidate members
    })
  ) //<-- end of the constructor call
}

You’ll also need to drop the as CandidateList from the end of that query after moving it into the constructor, otherwise you’ll either get an empty CandidateList or, possibly an ArgumentNullException from the List<T> base class of CandidateList. Notice that I’ve change the from; since you want the Candidates/Candidate nodes for the current Requests/Request, which is given by r.

Finally – all your property assignments to the Candidate object are coming from r – you need to change those to i (the product of the inner Linq statement).