Question

I have a mapped model with Nhibernate like this:

public class A
{
   public virtual long Id { get; set; }
   public virtual long Number { get; set; }

   /* and other 20 properties... */
}


public class B
{
   public virtual long Id { get; set; } 
   public virtual A ItemA { get; set; }
   public virtual string Name { get; set; }
   public virtual DateTime Date { get; set; }
}

I would like to create a query (queryover, linq, hql etc… anyway) to get a List<B> and fill ItemA property with just Id and Number properties because I need only this properties (I have lots of properties in A class and I will not use it on my results). Is there any way to do this or should I create a ViewModel? If I need to create a ViewModel, how can I do this with QueryOver?

Thank you!

Answer 1

Yes, you have to create a view model, like following:

public class BViewModel
{
    public virtual long Id { get; set; } 
    public virtual AViewModel ItemA { get; set; }
    public virtual string Name { get; set; }
    public virtual DateTime Date { get; set; }
}

public class AViewModel
{
    public virtual long Id { get; set; }
    public virtual long Number { get; set; }
}

Now you oculd query it with linq like this:

var listOfB = session.Query<B>()
    .Select(b => new BViewModel
        {
            Id = b.Id,
            Name = b.Name,
            Date = b.Date,
            ItemA = new AViewModel 
                {
                    Id = b.ItemA.Id,
                    Number = b.ItemA.Number,
                },
        }).ToList();