Create Multi-Select list of all Model Properties?

Question

In my MVC5 Code-First application, I am working on some Export to Excel Functionality using EPPlus. The View I'm working with is my ExportController - Index.cshtml view. The Model I'm attempting to loop through is my main Model, INV_Assets.

I saw the below posted in several similar questions (checkbox just for testing)

@foreach (var property in Model.GetType().GetProperties())
{
    @Html.Label(property.Name)
    @Html.CheckBox(property.Name)
}

but it is not rendering my Model Properties? For instance I have properties like [owner], [note], [description], etc, but the only thing rendered on my View are checkboxes titled "Capacity", "Count", and "Item"?

The following is my Controller Actions and my View:

ExportController - Index:

@using GridMvc.Html
@using System.Collections.Generic
@model  List<InventoryTracker.Models.INV_Assets>

@{
    ViewBag.Title = "Index";
    Layout = "~/Views/Shared/_Layout.cshtml";
}

<h2>Export</h2>

@*@foreach (var prop in Model.GetType().GetProperties())
{
    @(Html.TextBox(prop.Name, prop.GetValue(Model, null)))
}*@

@*@foreach(var property in ViewData.ModelMetadata.Properties)
{
    <label>@(property.DisplayName??property.PropertyName)</label>
    @Html.Editor(property.PropertyName)
}*@

@foreach (var property in Model.GetType().GetProperties())
{
    @Html.Label(property.Name)
    @Html.CheckBox(property.Name)
}


<a href="/Export/Export" class="btn btn-default btn-sm noDecoration"><span class="glyphicon glyphicon-export"> Export</span></a>
<br />
<br />
<a href="/Export/ExportUsingEPPlus" class="btn btn-default btn-sm noDecoration"><span class="glyphicon glyphicon-export"> Export - EPPlus</span></a>

ExportController:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;
using InventoryTracker.DAL;
using OfficeOpenXml;


namespace InventoryTracker.Controllers
{
    public class ExportController : Controller
    {
        InventoryTrackerContext _db = new InventoryTrackerContext();

        // GET: Export
        public ActionResult Index()
        {
            var assetList = _db.INV_Assets.ToList();
            return View(assetList);
        }

        public ActionResult Export()
        {
            GridView gv = new GridView();
            gv.DataSource = _db.INV_Assets.ToList();
            gv.DataBind();
            Response.ClearContent();
            Response.Buffer = true;
            Response.AddHeader("content-disposition", "attachment; filename=InventoryAssets-" + DateTime.Now + ".xls");
            Response.ContentType = "application/ms-excel";
            Response.Charset = "";
            StringWriter sw = new StringWriter();
            HtmlTextWriter htw = new HtmlTextWriter(sw);
            gv.RenderControl(htw);
            Response.Output.Write(sw.ToString());
            Response.Flush();
            Response.End();

            return RedirectToAction("StudentDetails");
        }

        public ActionResult ExportUsingEPPlus()
        {

            //FileInfo newExcelFile = new FileInfo(output);
            ExcelPackage package = new ExcelPackage();
            var ws = package.Workbook.Worksheets.Add("TestExport");
            ws.Cells["A1"].Value = "Sample Export 1";


            var memoryStream = new MemoryStream();
            package.SaveAs(memoryStream);

            string fileName = "Exported-InventoryAssets-" + DateTime.Now + ".xlsx";
            string contentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";

            memoryStream.Position = 0;
            return File(memoryStream, contentType, fileName);

        }

    }

    //https://stackoverflow.com/questions/5796151/export-model-data-to-excel-mvc
    //https://landokal.wordpress.com/2011/04/28/asp-net-mvc-export-to-excel-trick/


}

What I'm attempting to do is get a multi-select list of all my INV_Assets properties, and then export only those properties using EPPlus to Excel.

---

EDIT:

Code for Model INV_Assets:

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using GridMvc.DataAnnotations;
using System.Web.Mvc;
using InventoryTracker.Models;

namespace InventoryTracker.Models
{
    [GridTable(PagingEnabled = true, PageSize = 30)]
    public class INV_Assets 
    {
        // Setting GridColumn Annotations allows you to use AutoGenerateColumns on view to auto create the Grid based on the model.


        public int Id { get; set; }

        public int Model_Id { get; set; }
        [ForeignKey("Model_Id")]
        public virtual INV_Models Model { get; set; }

        [Required]
        public int Manufacturer_Id { get; set; }
        [ForeignKey("Manufacturer_Id")]
        public virtual INV_Manufacturers Manufacturer { get; set; }

        [Required]
        public int Type_Id { get; set; }
        [ForeignKey("Type_Id")]
        public virtual INV_Types Type { get; set; }

        [Required]
        public int Location_Id { get; set; }
        [ForeignKey("Location_Id")]
        public virtual INV_Locations Location { get; set; }

        public int Vendor_Id { get; set; }
        [ForeignKey("Vendor_Id")]
        public virtual INV_Vendors Vendor { get; set; }

        [Required]
        public int Status_Id { get; set; }
        [ForeignKey("Status_Id")]
        public virtual INV_Statuses Status { get; set; }

        public string ip_address { get; set; }

        public string mac_address { get; set; }

        [DataType(DataType.MultilineText)]
        public string note { get; set; }
        public string owner { get; set; }

        //[DataType(DataType.Currency)]
        //[DisplayFormat(DataFormatString="{0:C}", ApplyFormatInEditMode=true)]
        [DisplayFormat(DataFormatString = "{0:#,###0.00}", ApplyFormatInEditMode=true)]
        public decimal cost { get; set; }
        public string po_number { get; set; }

        [DataType(DataType.MultilineText)]
        public string description { get; set; }

        public int invoice_number{ get; set; }

        [Required]
        public string serial_number { get; set; }

        [Required]
        public string asset_tag_number { get; set; }

        [DataType(DataType.Date)]
        [DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
        public DateTime? acquired_date { get; set; }

        [DataType(DataType.Date)]
        [DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
        public DateTime? disposed_date { get; set; }

        [DataType(DataType.Date)]
        [DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
        public DateTime? verified_date { get; set; }

        [Required]
        [DataType(DataType.Date)]
        [DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
        public DateTime created_date { get; set; }

        [Required]
        public string created_by { get; set; }

        [DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}")]
        public DateTime? modified_date { get; set; }

        public string modified_by { get; set; }

        // Flag to specify if item is available? (Not signed out, not auctioned, recycled, etc.)
        //public bool available { get; set; }
    }
}

Answer 1

Try it like this:

@Html.ListBox("PropertyList", typeof(INV_Assets).GetProperties().Select(p => new SelectListItem { Text = p.Name, Value = p.Name, Selected = false })

EDIT:

Changed the type of the object on which GetProperties() is called. Before it was called on your Model which is a list. But what you are really trying to do is call it on the object type stored in the list.

EDIT 2:

Changed to ListBox instead of ListBoxFor. Since you are not using a view model, you will need to extract the selected items from the Request on POST. You could also add a List<string> propertyList parameter to your post action and it should bind automatically.

EDIT 3:

To get the data in a post action, you have to wrap your list box in a form, like this:

@using (Html.BeginForm("ExportProps", "Export") {
    @Html.ListBox(...)
}

Here is how to get the submitted data in the POST action:

[HttpPost]
public ActionResult ExportProps(List<string> propertyList) {
    // do stuff with your data here
}

The above code is not tested, but it should give an idea of how to handle the post.