Lookup value formatting

public class HomeController : Controller
{
    private DbContext Context { get; }

    public HomeController(DbContext context)
    {
        Context = context;
    }

    [HttpGet]
    public JsonResult People(LookupFilter filter)
    {
        return Json(new PeopleLookup(Context) { Filter = filter }.GetData());
    }
}

public class Person
{
    ...

    [Display(Name = "Birthday")]
    [LookupColumn(Format = "{0:d}")]
    public DateTime Birthday { get; set; }

    ...
}

public class PeopleLookup : ALookup<Person>
{
    private DbContext Context { get; }

    public PeopleLookup(DbContext context)
    {
        Context = context;
        FilterCase = LookupFilterCase.Lower;

        // Defaults to property with a name "Id".
        GetId = (model) => model.Id;

        // Defaults to first visible column.
        GetLabel = (model) => model.Name + " " + model.Surname;
    }

    public override IQueryable<Person> GetModels()
    {
        return Context.Set<Person>();
    }
}