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MVC ViewModel 2nd Model Posts Null?

I have a 'VendorViewModel' which displays data to the View without error. The 1st model (Vendor) returns data fine. The 2nd model (VendorType) is always null.

[ViewModel]

public class VendorViewModel
    {
        public Vendor vendor { get; set; }
        public VendorType vendorType { get; set; }
    }

public partial class Vendor
    {
        public Vendor()
        {
            this.Expenses = new HashSet<Expense>();
        }
    
        public System.Guid VendorID { get; set; }
        public string Name { get; set; }
        public System.Guid VendorTypeID { get; set; }
        public string Description { get; set; }
    
        public virtual ICollection<Expense> Expenses { get; set; }
        public virtual VendorType VendorType { get; set; }
    }

public partial class VendorType
    {
        public VendorType()
        {
            this.Vendors = new HashSet<Vendor>();
        }
    
        public System.Guid VendorTypeID { get; set; }
        public string Type { get; set; }
    
        public virtual ICollection<Vendor> Vendors { get; set; }
    }

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[View]

 @using (Html.BeginForm("New", "Vendor", FormMethod.Post, new { id = "form1" }))
            {
                <fieldset>
                    <legend>Add New Vendor To The List</legend>

                    <div class="editor-label">
                        @Html.LabelFor(model => model.vendor.Name, "Name")
                    </div>
                    <div class="editor-field">
                        @Html.EditorFor(model => model.vendor.Name, "Name")
                    </div>

                    <div class="editor-label">
                        @Html.Label("Type")
                    </div>
                    <div class="editor-field">
                        @Html.DropDownList("VendorTypeID", ViewBag.VendorTypeID as SelectList, "- select -")
                    </div>

                    <div class="editor-label">
                        @Html.LabelFor(model => model.vendor.Description, "Description")
                    </div>
                    <div class="editor-field">
                        @Html.EditorFor(model => model.vendor.Description, "Description")
                    </div>

                    <p>
                        <input type="submit" value="Save" />
                    </p>
                </fieldset>
            }

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[Action's]

 public ActionResult _New()
        {
            //Doesn't make any difference
            VendorViewModel viewModel = new VendorViewModel
            {
                vendor = new Vendor(),
                vendorType = new VendorType()
            };

            ViewBag.VendorTypeID = new SelectList(context.VendorTypes, "VendorTypeID", "Type");

            return View(viewModel);
        }

        public ActionResult New(VendorViewModel vvm)
        {
            if (ModelState.IsValid)
            {
                context.VendorTypes.Add(vvm.vendorType); // NULL
                context.Vendors.Add(vvm.vendor); 
                context.SaveChanges();
                return RedirectToAction("_New");
            }

            return View("_New");
        }

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Bob Learned

You are doing something custom, so the property names won't line up:

<div class="editor-field">
                        @Html.DropDownList("VendorTypeID", ViewBag.VendorTypeID as SelectList, "- select -")
</div>

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Try using the HtmlHelper.DropDownListFor:

Html.DropDownListFor(m => m.ModelType, 
                new SelectList(Model.ModelTypeOptions, 
                               "ModelId", "Value", 
                               Model.ModelTypeOptions.First().ModelId))

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WorknHardr

ASKER

hmm, what is 'ModelTypeOptions'???

Bob Learned

Sorry, that was an example without context. SelectList constructor takes any list that implements IEnumerable.

I believe that would be equivalent to this:

new SelectList(context.VendorTypes, "VendorTypeID", "Type");

WorknHardr

ASKER

That's what I thought, just unsure how to get 'context' within the View. I do this in the controller like so:

BudgetProjectEntities context = new BudgetProjectEntities();
context.VendorTypes

ASKER CERTIFIED SOLUTION

Bob Learned

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WorknHardr

ASKER

Excellent, I lean something new everyday, thx