Question

var store = GetStore();
using (IsolatedStorageFileStream fileStream = store.OpenFile(RootData, FileMode.Create))
{
DataContractSerializer serializer = new DataContractSerializer(typeof(List));
serializer.WriteObject(fileStream, rootdatalist);
}

But this only serializes the rootdatalist, and not the subitems. The rootdatalist has a nodes List property, how do I serialize that, so that I get the list hierarchy serialized?

Since it’s dbml generated objects the Nodes property of Root is

public System.Data.Linq.Table<Node> Nodes
{
    get
    {
        return this.GetTable<Node>();
    }
}

My Datacontext return is:

public List<Root> GetRootList(Guid userid)
{
   DataLoadOptions loadopts = new DataLoadOptions();
   loadopts.LoadWith<Root>(s => s.Nodes);
   this.DataContext.LoadOptions = loadopts;
   return this.DataContext.Root.Where(s => s.Nodes.Count(n => n.UserId == userid) > 0).ToList();
}

the Node entityset looks as follows in my dbml designer

[global::System.Data.Linq.Mapping.AssociationAttribute(Name="Root_Node", Storage="_Nodes", ThisKey="Id", OtherKey="RootId")]
[global::System.Runtime.Serialization.DataMemberAttribute(Order=5, EmitDefaultValue=false)]
public EntitySet<Node> Nodes
{
    get
    {
        if ((this.serializing && (this._Nodes.HasLoadedOrAssignedValues == false)))
        {
            return null;
        }
        return this._Nodes;
    }
    set
    {
        this._Nodes.Assign(value);
    }
}

Also I have to have the [Include]tag above my properties or nothing will be loaded.
Edit::
To others wanting to serialize dbml classes Link

Answer 1

Can you include any more information about the contract types? I would expect, for example, that Root is marked as a data-contract, with the member as a data-member, for example:

[DataContract]
public class Root {
    [DataMember]
    public List<SubItem> Nodes {get;private set;}
}

[DataContract]
public class SubItem {
    [DataMember]
    public int Foo {get;set;}

    [DataMember]
    public string Bar {get;set;}
}

That should then work. If not, it would really help to see your types (or a cut-down version of them, that illustrates the problem).