C＃实体框架：选择后获取子项的父级

Question

I'm trying to 'keep' the reference to the parent in the object after a query to EF starting by the parent entity while filtering on the both parent and children and returning the children. But those children records i'm returning need to maintain their reference back to the parent.

In the example below, the parent is available 'up until the select' is performed, and then the children are returned... but the reference 'back' to the parent is lost. HOW can i not loose that object of the parent???

so what i need is that the return result of Table2Model, still holds reference back to parent in the MODEL.. but after the select statement that reference is lost.

if i add this

result.ForEach((t2) =>
  {
    t2.Table1 = db.Table1Model.SingleOrDefault(t1 => t1.Table1Id == t2.Table1Id);
  });

it fixes my problem... but i was wondering if there was some way to retain the parent reference in the original call. Doing this in two steps doubles the work effort of the query.

(db below is the database context)

public class Table1Model {
    public Table1Id {get; set;}
    public Name {get; set;}
    public Desc {get; set;}
    public virtual ICollection<Table2Model> Table2Models {get; set;}
}

public class Table2Model {
    public Table2ModelId {get; set;}
    public SpecialData1 {get; set;}
    public SpecialData2 {get; set;}
    public SpecialData3 {get; set;}
    public Table1Id {get; set;}
    public virtual Table1Model Table1 {get; set;}
}

public class List<Table2Model> DoWork(sampleRequest request){

    var result = db.Table1Model
        .Where(t => t.Name = request.Name)
        .Select(t => t.Table2Models.OrderByDescending(n => n.Table2ModelId).FirstOrDefault())
        .OrderBy(t2 => t2.SpecialData1)
        .Take(5)
        .ToList();

    return result;
}

Answer 1

Perhaps I'm missing something here, but why not project into a different model and include both pieces.

public class TheModel
{
    public Table1Model Table1Model { get; set; }
    public Table2Model Table2Model { get; set; }
}

var result = db.Table1Model
    .Where(t => t.Name = request.Name)
    .Select(t => new TheModel {
        Table1Model = t,
        Table2Model = t.Table2Models
            .OrderByDescending(n => n.Table2ModelId)
            .FirstOrDefault())
    .OrderBy(t2 => t2.Table2Model.SpecialData1)
    .Take(5)
    .ToList();

I'd actually suggest you break down TheModel into just the specific properties you need and be a little more granular with the request, but I don't know what exactly you need to can't give a more specific example.