how to use model binder to post data from a form + value of a span to data base

Good time. I'm new in Asp.net-MVC .

I have a form which it gets data from user and there is a span in this page which I want to post data of inputs and value of span to my data base.

I wanted to use model binder but I don't know how to name spans same as my model.

here is my action :

[HttpPost]
    [ValidateAntiForgeryToken]
    public ActionResult Create([Bind(Include = "Id,TourId,FirstName,LastName,Email,Phone,Comment,FrequentTraveler,TravelersCount,Date,ContactTimePreference,Country,Archived")] Request request)
    {
        if (ModelState.IsValid)
        {
            db.Requests.Add(request);
            db.SaveChanges();
            return RedirectToAction("Index");
        }

        return View(request);
    } 

span is getting value from JavaScript

<span class="col-md-5" id="selecteddate"></span>

and here is my form but I write just one of the inputs here for Shorthand. :

 <form role="form" method="post" action="/Tour">
  @Html.AntiForgeryToken()

 <div class="form-group">
 <label for="FName">First Name:</label>
 <input type="text" name="FirstName" class="form-control" id="FName" placeholder="Enter FirstName" />


 </div>

</form>

I want to post value of span id="selecteddate" to data base in column named Date

appreciate if any one could tell me how it could be possible or if you have any better way as suggestion?

One solution for this is, add a hidden html input to your <from>. When you do your submit, you write its value as a copy from your span using javascript.

<form role="form" method="post" action="/Tour" onsubmit="prepare()">
  @Html.AntiForgeryToken()

 <div class="form-group">
 <label for="FName">First Name:</label>
 <input type="text" name="FirstName" class="form-control" id="FName" placeholder="Enter FirstName" />


 </div>
<input type="hidden" name="Date" />
</form>

@section Scripts {
  <script type="text/javascript">
    function prepare() {
        document.getElementsByName("Date")[0].value = document.getElementById("selecteddate").innerHtml;
    }
  </script>
}