Question

I’ve just started using LINQ and I’m having a couple of problems understanding how to read recursively from an XML file

If I have XML similar to

> <ProjectTemplates>
>   <ProjectTemplate Name="Standard">
>         <DeliverableTemplates>
>           <DeliverableTemplate Name="Each Deliverable">
>             <DependantDeliverables>
>               <DeliverableTemplate Name="Can Have a Collection">
>                 <DependantDeliverables>
>                   <DeliverableTemplate Name="of dependant deliverables">
>                     <DependantDeliverables>
>                       <DeliverableTemplate Name="recursively">
>                         <DependantDeliverables />
>                       </DeliverableTemplate>
>                     </DependantDeliverables>
>                   </DeliverableTemplate>
>                 </DependantDeliverables>
>               </DeliverableTemplate>
>             </DependantDeliverables>
>           </DeliverableTemplate>
>         </DependantDeliverables>
>       </DeliverableTemplate>
>     </DependantDeliverables>
>   </DeliverableTemplate>
> </ProjectTemplates>

And I’m trying to read this into a couple of really simple classes

internal class Project
{
    public string Name;
    public List<Deliverable> Deliverables;
}
internal class Deliverable
{
    public string Name;
    public List<Deliverable> DependantDeliverables;

    public Deliverable()
    {
        DependantDeliverables = new List<Deliverable>();
    }
}

But I’m really not sure how to go about it. This is as far as I’ve got

var xmlProjects = XElement.Load(XMLPath);
var projecttemplates =
(
    from el in xmlProjects.Elements("ProjectTemplates").Elements("ProjectTemplate")
    select new Project
    {
        Name = el.Attribute("Name").Value,
        Deliverables =
        (
            from elDeliverables in el.Elements("DeliverableTemplates").Elements("DeliverableTemplate")
            select new Deliverable
            {
                Name = elDeliverables.Attribute("Name").Value,
                DependantDeliverables = new List<Deliverable>()   
            }
        ).ToList<Deliverable>()
    }
).ToList<Project>();

I’m having problems building the list of DependantDeliverables. I’m not even sure whether I can do it as a single statement like this.

Can someone please help?

Jason

Answer 1

I would change the Deliverable class so that its constructor takes in the XElement corresponding to a given <DeliverableTemplate>. That constructor will then be responsible for traversing the XElement, looking for children, populating the List<>, and invoking further constructors further passing in more XElements until you’ve reached and parsed all your nodes.