从PartialView MVC4获取数据

Question

I'm working with (ASP.Net MVC4), and I'm stuck in how to get info from partial view. I mean I have a my viewmodel

public class ShowHomeViewModel
{
    public int ID_ClientTypeID { get; set; }
    public string ReservationDate { get; set; }
    public short ClientNum { get; set; }
            public string ClientPhone { get; set; }

    public List<HomeViewModel> ReservedHuts { get; set; }
}

I have a partial view where I'm showing all de data from HomeViewModel, it show's great, the problem is when I try to recover the list of ReservedHuts from the view:

@model HutReservation.ViewModel.ShowHomeViewModel
    <table>
        <tr>
            @{Html.RenderPartial("_Reservations", Model.ReservedHuts);}
        </tr>
    </table>

In my view I show the list and change some data, but when I click on the button and go to the New Method bellow, turns out that the ReservedHuts (the list of HomeViewModel) is null

[HttpPost] //cambiar la pagina para el partial view
    public ActionResult New(ShowHomeViewModel vm) // <- this vm is null
    {

        foreach (HomeViewModel hvm in vm.ReservedHuts)
        {

        }
        return View("ConfirmNew", vm);
    }

I'm really stuck here, Thanks for your help in advance

Answer 1

The problem here is that your form data cannot be bound to ShowHomeViewModel . This is because the context of Model has changed when you render your partial (the model context has changed from ShowHomeViewModel to HomeViewModel). MVC uses conventions to bind the properties by default (you can make your own model binders if you wish, which use whatever methods you want to bind). By Default, when you make an EditorFor a property of your model, MVC will name the form field appropriate so that it can be bound back to the model context it was created from.

So if you skip the partial, you can just run your foreach in the parent view, and you could probably still bind to ShowHomeViewModel because it will name the form fields like this:

<input name="ReservedHuts_HutId">

However, if you use the partial and change your model context, it will render the same input like this:

<input name="HutId">

So, MVC cannot (by default) bind the value of HutId to ShowHomeViewModel because there is no property called HutId (But there is HutId property on HomeViewModel, so it will bind successfully!)