Return model from Partial View issue - asp.net-mvc

Question

I have created a partial view (even though the editor template), I pass a sub model to the view, however, when I clicked "submit", I always get "null" from the partial view. I can get Main model's properties values except the sub model one.
Main Model
public class PetModel
{
public string name {get; set;}
public long SpeciesID {get; set;}
public long BreedID {get; set;}
public Calendar DOB {get; set;}
}
Sub Model
public class Calendar
{
public string Year{get; set;}
public string Month{get; set;}
public string Day{get; set;}
}
Main View
#model Application.Models.PetModel
#using (Html.BeginForm("CatchPetContent", "Quote",Model))
{
#Html.TextBoxFor(x => x.Name)
#Html.DropDownListFor(x=>x.SpeciesID,new List<SelectListItem>(),"select")
#Html.DropDownListFor(x=>x.BreedID,new List<SelectListItem>(),"select")
#Html.EditorFor(Model => x.DOB)
<input type="submit" value="submit" />
}
Editor template
#model Application.Models.Calendar
#Html.DropDownListFor(Model => Model.Day, new List<SelectListItem>())
#Html.DropDownListFor(Model => Model.Month,new List<SelectListItem>())
#Html.DropDownListFor(Model => Model.Year, new List<SelectListItem>())
"CatchPetContent" action
[HttpPost]
public ActionResult CatchPetContent(PetModel Model)
{
PetModel pet = new PetModel();
pet.Name = Model.Name;
pet.SpeciesID = Model.SpeciesID;
pet.BreedID = Model.BreedID;
pet.DOB = Model.DOB;// always null
RouteValueDictionary redirectTargetDictionary = new RouteValueDictionary();
redirectTargetDictionary.Add("Controller", "Home");
redirectTargetDictionary.Add("Action", "Index");
return new RedirectToRouteResult(new RouteValueDictionary(redirectTargetDictionary));
}
When I debugged it, "Model.DOB" is always null

Answer 1

You should add the sub-property as an extra parameter on your action:
[HttpPost]
public ActionResult CatchPetContent(PetModel Model, Calendar Bob)
{
** snip **
}
The default ModelBinder doesn't nest the objects. It does however find the values if you include it as a second parameter.
If you want to nest them, you'd have to create your own modelbinder.
The following question had a similar issue: List count empty when passing from view to model in ASP.Net MVC

Answer 2

The default model binder will bind nested objects, you do not need to create your own model binder for this scenario.
See:
http://lostechies.com/jimmybogard/2011/09/07/building-forms-for-deep-view-model-graphs-in-asp-net-mvc/
and on SO
DefaultModelBinder not binding nested model
I suspect your problem is that your editor template is not returning anything via the post back so the nested object is null. The lines in your editor template:
#Html.DropDownListFor(Model => Model.Day, new List<SelectListItem>())
#Html.DropDownListFor(Model => Model.Month,new List<SelectListItem>())
#Html.DropDownListFor(Model => Model.Year, new List<SelectListItem>())
Will give you three controls with empty drop downs, you will not be able to select anything from these drop downs as you have not supplied any values to them. If there is no value then they are not sent across the wire and cannot be model bound. To start of with change you editor template to:
#Html.TextBoxFor(Model => Model.Day)
#Html.TextBoxFor(Model => Model.Month)
#Html.TextBoxFor(Model => Model.Year)
This will allow you to actually enter some data onto to form. Once this is working you can then change the text boxes back to drop downs but you will need to supply values for the select lists, again, just creating new empty lists will not allow you to select any values.

Answer 3

instead of
#Html.EditorFor(Model => x.DOB)
try render partial view
#Html.Partial("partialViewName", Model.DOB)

Answer 4

I think in your Main View you have a typo, it looks like you should change
#Html.EditorFor(Model => x.DOB)
to
#Html.EditorFor(x => x.DOB)