How to code a viewModel with nested classes

Question

My web page / view will have 1 to many import records. Within each import record will be 0 to many of the following:

• Purchase Orders
• Shipping Containers
• Products
• Invoices

I have coded my view model as follows:

namespace LemansCorpIntranet.Models
{    
    public class ImportWebViewModel
    {
        public string button { get; set; }
        public string status_filter { get; set; }
        public string import_id_filter { get; set; }
        public DateTime date_filter { get; set; }
        public string vendor_filter { get; set; }
        public string port_filter { get; set; }
        public string whse_filter { get; set; }
        public Boolean not_released_filter { get; set; }
        public int release_gap { get; set; }
        public List<import_row> import_rows;
    }

    public class import_row
    {
        public string update_switch { get; set; }
        public string id { get; set; }
        public IEnumerable<SelectListItem> ship_via { get; set; }
        public string broker_number { get; set; }
        public string voyage { get; set; }
        public string vessel { get; set; }
        public decimal shipment_value { get; set; }
        public int cartons { get; set; }
        public decimal weight { get; set; }
        public decimal volume { get; set; }
        public string clearance_port { get; set; }
        public string warehouses_in_shipment { get; set; }
        public string payment_type { get; set; }
        public string insurance { get; set; }
        public DateTime ship_date { get; set; }
        public DateTime close_date { get; set; }
        public DateTime customs_date { get; set; }
        public string customs_entry { get; set; }
        public DateTime pl_2_whse_date { get; set; }
        public DateTime estimated_arrival_date { get; set; }
        public DateTime wire_transfer_request_done_date { get; set; }
        public DateTime approved_broker_bill_date { get; set; }
        public DateTime product_released_date { get; set; }
        public List<Invoice> Invoices;
        public List<PurchaseOrder> PurchasOrders;
        public List<Product> Products;
        public List<Container> Containers;
    }

    public class Invoice
    {
        public string invoice_number { get; set; }
    }

    public class PurchaseOrder
    {
        public string id { get; set; }
        public string whse { get; set; }
        public string vendor_code { get; set; }
        public string vendor_name { get; set; }
    }

    public class Product
    {
        public int line_number { get; set; }
        public string description { get; set; }
    }

    public class Container
    {
        public int line_number { get; set; }
        public int size { get; set; }
        public string id { get; set; }
        public string seal { get; set; }
        public DateTime received_date { get; set; }
        public int cartons { get; set; }
    }  
}

Is the above OK? Are the classes nested correctly?

I can get the view to display my data from the server correctly, but when I "post" the form the data in the nested classes is null.

I believe this is because the input controls don't get built as they need to be.

My view is similar to the following:

<table>
<% if (Model.import_rows != null)
   { %>
<%    for (int row = 0; row < Model.import_rows.Count; row++)
      { %>
        <tr><td>
                <%=Html.HiddenFor(x=>x.import_rows[row].id) %>
                <%=Html.TextBoxFor(x => x.import_rows[row].id)%>
            </td>
        </tr>
<%    } %>
<% } %>
</table>

Any suggestions would be greatly appreciated....

Update: I have changed my view to include "hiddenFor" items.

"import_rows" is no longer null in the controller, but the count is "0". I still must be missing something.....

Thanks in advance.

Answer 1

I was attempting to pass the viewmodel in a RedirectToAction..

Have discovered this doesn't work that way.

Thanks everyone for your assistance.