MVC4 Entity Framework -- How do I display One-to-Many Relationships - asp.net-mvc

Question

I have a class with with one-to-many relationship and trying to display the virtual object in the view. I am fairly new to MVC and EF so this maybe something simple.
I am trying to display a drop down list for PODObject on "Request/Create" action view.
Here are the models
public class PODObject
{
public int PODObjectID { set; get; }
public string name { set; get; }
public string CustomAttribute1 { set; get; }
public string CustomAttribute2 { set; get; }
public string CustomAttribute3 { set; get; }
public string CustomAttribute4 { set; get; }
public string CustomAttribute5 { set; get; }
public virtual ICollection<BookingObject> BookingObjectspublic { set; get; }
}
public class RequestsQueueObject
{
// Request Attributes
public int RequestsQueueObjectID { set; get; }
public string CustomAttribute1 { set; get; }
public string CustomAttribute2 { set; get; }
public string CustomAttribute3 { set; get; }
public string CustomAttribute4 { set; get; }
public string CustomAttribute5 { set; get; }
public int PODObjectID { set; get; }
public virtual PODObject PODObject { set; get; }
}
Here is the controller Create action
public ActionResult Create([Bind(Include="RequestsQueueObjectID,POCPODAccess,CustomAttribute1,CustomAttribute2,CustomAttribute3,CustomAttribute4,CustomAttribute5")] RequestsQueueObject requestsqueueobject)
{
if (ModelState.IsValid)
{
db.RequestsQueueObjects.Add(requestsqueueobject);
db.SaveChanges();
return RedirectToAction("Index");
}
return View(requestsqueueobject);
}
Here is the cshtml
<div class="form-group">
#Html.DropDownListFor(model => model.PODObject, new { #class = "control-label col-md-2" })
<div class="col-md-10">
#Html.EditorFor(model => model.PODObject)
#Html.ValidationMessageFor(model => model.PODObject)
</div>
</div>

Answer 1

Maybe I am wrong but your PODOObject doesn't look like a List, an Array or whatever, so you can't really use it as a source for your dropdown...

Answer 2

I think what you're looking for is being able to pick from a list of existing PODObject instances to set as the related item for RequestQueueObject. You've got a few issues you need to clear up for that.
You have a property on RequestQueueObject to hold the id for the relationship with PODObject, but this currently isn't being used. Entity Framework's convention is to look for an property with the naming pattern [RelatedProperty][RelatedClassIdProperty]. In your scenario, that would be PODObjectPODObjectID or PODObject_PODObjectID. You can clear that up by adding the ForeignKey attribute to your PODObjectID property:
[ForeignKey("PODObject")]
public int PODObjectID { get; set; }
Html.DropDownListFor requires an IEnumerable<SelectListItem> for its second parameter, which you don't currently have. MVC won't do this for you; you need to create the list of choices yourself. Ideally, you would use a view model with this as a property, but for the time being, you can use ViewBag:
In your action
var podObjectChoices = db.PODObjects.Select(m => new SelectListItem
{
Value = m.PODObjectID,
Text = m.name
});
ViewBag.PODObjectChoices = podObjectChoices.ToList();
return View();
In your view
#Html.DropDownListFor(m => m.PODObjectID, (IEnumerable<SelectListItem>)ViewBag.PODOBjectChoices, new { #class = "control-label col-md-2" })
I pretty much just covered this in the sample code above, but you can't directly set PODOBject via a drop down list. Instead, you set the foreign key property for the relationship, PODOBjectID, and Entity Framework will wire it up.