Why doesn't the model go from the view to the controller?

Question

ASP.NET

Hello!
asp mvc 6.
Everything seems to be correct, but for some reason, when submitting, null comes to the controller.

//открываю представление с списком моделей

 public ActionResult Banners()
        {
            List<BusinessLayer.Events.Banners> BannersMdl = new List<BusinessLayer.Events.Banners>();

BannersMdl = BusinesLogic.GetBanners();          

            return View(BannersMdl);
        }

the list of models goes to the view, everything is filled in:

@model IEnumerable<BusinessLayer.Events.Banners>


        @using (Html.BeginForm("Banners", "AD", FormMethod.Post))              
                {


                    <fieldset>

                       @foreach (var Ad in Model)
                       {
                           switch (Ad.TypeBanner)
                           {

                               case 1:
                                <h4>Большой главный AD1</h4>
                                   break;

                               case 2:
                                <h4>Событие сайдбар ПК AD2</h4>
                                   break;

                               case 3:
                                <h4>Событие сайдбар мобильный AD3</h4>
                                   break;

                               case 4:
                                <h4>Событие шапка ПК AD4</h4>
                                   break;

                               case 5:
                                <h4>Событие шапка мобильный AD5</h4>
                                   break;

                           }

                      


                        @Html.TextAreaFor(m => Ad.Html, new { @class = "Width500", @style = "height:130px;" })<br><br>

                       }

                     
                      
                       
                         


                        <center> <div style="font-size:large;" id="msg">  </div></center>
                        <p>
                            <input type="submit" id="getCoordsButton" style="float:left" value="Сохранить" />


                            <span id="sendingProgress" style="display: none;">
                                Сохранение...
                                <img src='@Href("~/Images/TEMPLATE/ANIMATIONS/load0.GIF")' />
                            </span>
                        </p>

                    </fieldset>


                            }

accept view with new data on submit

[HttpPost]
        [HttpPost]     
        public ActionResult Banners(List<BusinessLayer.Events.Banners> BannersMdl)
        {
.....

and here BannersMdl = null.

Answer 1

Most likely, the names of the HTML elements are incorrect (the same). Try using a regular for , then the output should be names with an index (type: [0].Html , [1].Html , etc.):

@for (int i = 0, count = Model.Count; i < count; ++i)
{
  @Html.TextAreaFor(m => m[i].Html, new { @class = "Width500", @style = "height:130px;" })
}