Save multiple rows simultaneously from the same form

Hi Guys,

I really hope you will be able to help me with this, I am still learning and can't get my head around this problem.

I have a table that has one empty column into which user can enter a comment. Since there is a lot of data for them to comment on, I can't really expect them to open an 'Edit' page and fill in comment one by one. Instead I need them to be able to input a bunch of comments (say 20 at a time against 20 rows) and save them all at one click of submit button.

Some aspects of .net core are still alien to me, I am still learning. Here is what I tried:

View (please note that the first table is only there to display info, its the second table that has one input field per row)

@using ASPNET_Core_1_0.Models.TbMapViewModels;
@model TbMapViewModel
@{
}<div class="wrapper wrapper-content animated fadeInRight"><div class="row"><div class="col-lg-6"><div class="row"><div class="col-md-12"><table class="table table-condensed table-bordered table-hover"><thead><tr><td><b>Expense Description</b></td><td><b>Dealership</b></td><td><b>Unique ADP Code</b></td></tr></thead><tbody>
                            @foreach (var item in Model.TBMapUniqueADP)
                            {<tr><td>@item.ExpenseDescriptionU</td><td>@item.DealershipU</td><td>@item.UniqueAdpU</td></tr>
                            }</tbody></table></div></div></div><form asp-action="TbMapViewEdit"><div class="col-lg-6"><div class="row"><input type="submit" value="Save" class="btn btn-primary" /><div class="col-md-12"><table class="table table-condensed table-bordered table-hover"><thead><tr><td><b>TEMP ID</b></td><td><b>Map To</b></td><td><b>Accounts Code</b></td><td><b>Line</b></td><td><b>Map Result</b></td></tr></thead><tbody>
                                @for (int i = 0; i < Model.TBMapBalances.Count; i++)
                                {<tr><td>
                                            @Html.DisplayFor(Model => Model.TBMapBalances[i].TbMapId)
                                            @Html.HiddenFor(Model => Model.TBMapBalances[i].TbMapId)</td><td>@Html.EditorFor(Model => Model.TBMapBalances[i].UniqueAdp, new { @class = "control-label_DI" })</td><td>@Html.DisplayFor(Model => Model.TBMapBalances[i].AccountsCode)</td><td>@Html.DisplayFor(Model => Model.TBMapBalances[i].Line)</td><td>@Html.DisplayFor(Model => Model.TBMapBalances[i].MapResult)</td></tr>
                                }</tbody></table></div></div></div></form></div></div>

Model

I've learned today that I need to use List to be able to iterate through the lines in table by the use of @for loop (as shown above). before I was trying to use IEnumerable. So I added a definition to the model for public List<TBMapBalances> TBMapBalances { get; set; }

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace ASPNET_Core_1_0.Models.TbMapViewModels
{
    public class TbMapViewModel
    {
       // public IEnumerable<ASPNET_Core_1_0.Models.TBMapBalances> TBMapBalances { get; set; }
        public IEnumerable<ASPNET_Core_1_0.Models.TBMapUniqueADP> TBMapUniqueADP { get; set; }
        public List<TBMapBalances> TBMapBalances { get; set; }

        public ASPNET_Core_1_0.Models.TBMapBalances TbMapId { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances UniqueAdp { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances DlrCode { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances Dealership { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances UnqDept { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances AccountsCode { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances ExpenseDescription { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances BFwd { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances CurrentMth { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances CFwd { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances Future { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances ClientDepartment { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances AccountsTab { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances Area { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances ACode { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances AreaSub { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances AsCode { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances Line { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances ImpCode { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances DcCode { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances F20 { get; set; }
        public ASPNET_Core_1_0.Models.TBMapBalances MapResult { get; set; }

        public ASPNET_Core_1_0.Models.TBMapUniqueADP TbMapUniqueId { get; set; }
        public ASPNET_Core_1_0.Models.TBMapUniqueADP UniqueAdpU { get; set; }
        public ASPNET_Core_1_0.Models.TBMapUniqueADP DealershipU { get; set; }
        public ASPNET_Core_1_0.Models.TBMapUniqueADP ExpenseDescriptionU { get; set; }

    }
}

Controller:

Now this is where I need the help with, my code doesn't throw any errors at all when at the current state - when I press Submit nothing happens and no data gets saved to the database.

however, when you uncomment line  _context.Update(tbMapViewModel.TBMapBalances);  I get an error that List<TBMapBalances> is not part of any Model and is not found.

Also, below code is something I wrote trying to follow this SO post: update-multiple-records-at-once-in-asp-net-mvc - Initially I was trying to make it Async but I was getting even more errors and couldn't continue. I thought I am going to follow it as closely as possible in hope that it will get me a working starting point.

    public class TbMapController : Controller
    {
        private readonly FPSDemoContext _context;

        public TbMapController(FPSDemoContext context)
        {
            _context = context;
        }

        [Authorize]
        public async Task<IActionResult> TbMapView()
        {
            var model = new TbMapViewModel
            {
                TBMapBalances = await _context.TBMapBalances.Where(x => x.AccountsCode == "bstvx-bca-stk-ptstk-v").ToListAsync(),
                TBMapUniqueADP = await _context.TBMapUniqueADP.Where(x => x.DealershipU == "Derby").ToListAsync(),
               // TBMapBalancesList = await _context.TBMapBalances.Where(x => x.AccountsCode == "bstvx-bca-stk-ptstk-v").ToListAsync()
            };

            return View(model);
        }

        [Authorize]
        [HttpPost]
        public IActionResult TbMapViewEdit(TbMapViewModel tbMapViewModel)
        {

            if (ModelState.IsValid)
            {
                foreach (var TbListId in tbMapViewModel.TBMapBalances)
                {
                    var getCode = _context.TBMapBalances.Where(p => p.TbMapId == TbListId.TbMapId).FirstOrDefault();

                    if (getCode != null)
                    {
                        getCode.TbMapId = TbListId.TbMapId;
                    }

                }
               // _context.Update(tbMapViewModel.TBMapBalances);
                _context.SaveChanges();

            }

            return RedirectToAction("TbMapView");
        }



        [Authorize]
        public IActionResult DragDemo()
        {
            return View();
        }

        private bool TbMapBalancesExists(int? Id)
        {
            return _context.TBMapBalances.Any(e => e.TbMapId == Id);
        }

    }

I am so desperate now to learn how to do this, how to save multiple rows at the sime time from the form.

Thanks for any help!!