Nested object null on client side in CODE FIRST EF RIA Service - entity-framework

Question

I have nested object in EF Code First using Silverlight RIA service, I am able to get the data at service side but when I see it on client side child objects are null. Could you please guide me what's wrong.
[HasSelfValidation]
public class Batch
{
public int BatchId { get; set; }
public string BatchName { get; set; }
[Include]
[Composition]
[Association("FK_Batch_BathSetItemSet", "BatchId", "BatchSetIdItemSetId")]
public virtual ICollection<BatchSetItemSet> BatchSetItemSets { get; set; }
}
public class BatchSetItemSet
{
public int BatchSetIdItemSetId { get; set; }
public int BatchId { get; set; }
public Nullable<int> ItemSetId { get; set; }
public string CreatedBy { get; set; }
public Batch Batch { get; set; }
[Include]
[Composition]
[Association("FK_BathSetItemSet_ItemSet", "BatchSetIdItemSetId", "ItemSetId")]
public ItemSet ItemSet { get; set; }
}
public class ItemSet
{
public int ItemSetId { get; set; }
public int CustodianId { get; set; }
public string ItemSetName { get; set; }
public virtual ICollection<BatchSetItemSet> BatchSetItemSets { get; set; }
[Include]
[Composition]
[Association("FK_ItemSet_Custodian", "ItemSetId", "CustodianId")]
public virtual Custodian Custodian { get; set; }
}
and service call is : this.DbContext.Batches.Include("BatchSetItemSets.ItemSet.Custodian").Where(x => x.BatchId == batchId).SingleOrDefault();

Answer 1

You are close with the attributes, but they need to be changed:
[HasSelfValidation]
public class Batch
{
public int BatchId { get; set; }
public string BatchName { get; set; }
[Include]
[Composition]
[Association("FK_Batch_BathSetItemSet", "BatchId", "BatchId", IsForeignKey = false)]
public virtual ICollection<BatchSetItemSet> BatchSetItemSets { get; set; }
}
public class BatchSetItemSet
{
public int BatchSetIdItemSetId { get; set; }
public int BatchId { get; set; }
public Nullable<int> ItemSetId { get; set; }
public string CreatedBy { get; set; }
[Include]
[Association("FK_Batch_BathSetItemSet", "BatchId", "BatchId")]
public Batch Batch { get; set; }
[Include]
[Association("FK_BathSetItemSet_ItemSet", "ItemSetId", "ItemSetId")]
public ItemSet ItemSet { get; set; }
}
public class ItemSet
{
public int ItemSetId { get; set; }
public int CustodianId { get; set; }
public string ItemSetName { get; set; }
[Include]
[Composition]
[Association("FK_BathSetItemSet_ItemSet", "ItemSetId", "ItemSetId", IsForeignKey = false)]
public virtual ICollection<BatchSetItemSet> BatchSetItemSets { get; set; }
[Include]
[Association("FK_ItemSet_Custodian", "CustodianId", "CustodianId")]
public virtual Custodian Custodian { get; set; }
}
The AssociationAttribute .ctor is defined as:
AssociationAttribute(string name, string thisKey, string otherKey)
It should be configured as:
name: A unique name shared by each end of the relationship
thisKey: The name of the Property on this object that represents the key or foreign key
otherKey: The name of the Property on the other object that represents the key or foreign key
IsForeignKey: A property on AssociationAttribute to indicate if this end of the relationship is the primary key or the foreign key. It defaults to true (meaning this navigation property is a Foreign Key). By setting it to false, you indicate to WCF RIA that this object contains the Primary Key. For all AssociationAttribute usages with a given name, only one is allowed to have IsForeignKey = false. Otherwise, you will get a build error.