Model binding null values in MVC Core - asp.net-mvc

Question

I am trying to post data from form to action method but looks like model binder is not binding to the entities and I am getting null values in the action method, your help is much appreciated
please find the code snippet below.
Action method
[HttpPost]
public async Task<IActionResult> Update(EditRoleViewModel model)
{
if (ModelState.IsValid)
{
var role = await _Roleame.FindByIdAsync(model.Id);
if (role == null)
{
return RedirectToAction("notfound");
}
role.Name = model.RoleName;
var result = await _Roleame.UpdateAsync(role);
if (result.Succeeded)
{
return RedirectToAction("getAllRoles", "Administrator");
}
}
else {
ModelState.AddModelError(string.Empty, "Error");
}
return View();
}
Model
public class EditRoleViewModel
{
public EditRoleViewModel()
{
names = new List<string>();
}
public string Id;
[Required]
public string RoleName;
public List<string> names;
}
View
#model FirstCoreApplication.Model.EditRoleViewModel
<script src="~/twitter-bootstrap/js/bootstrap.js"></script>
<link href="~/twitter-bootstrap/css/bootstrap.css" rel="stylesheet" />
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css" integrity="sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh" crossorigin="anonymous">
#{
ViewBag.Title = "Edit Role";
}
<h1>Edit Role</h1>
<form method="post" class="mt-3" asp-controller="Administrator" asp-action="Update">
<div class="form-group row">
<label asp-for="Id" class="col-sm-2 col-form-label"></label>
<div class="col-sm-10">
<input asp-for="Id" disabled class="form-control">
</div>
</div>
<div class="form-group row">
<label asp-for="RoleName" class="col-sm-2 col-form-label"></label>
<div class="col-sm-10">
<input asp-for="RoleName" class="form-control">
<span asp-validation-for="RoleName" class="text-danger"></span>
</div>
</div>
<div asp-validation-summary="All" class="text-danger"></div>
<div class="form-group row">
<div class="col-sm-10">
<button type="submit" class="btn btn-primary">Update</button>
<a asp-action="ListRoles" class="btn btn-primary">Cancel</a>
</div>
</div>
<div class="card">
<div class="card-header">
<h3>Users in this role</h3>
</div>
<div class="card-body">
#if (Model.names.Any())
{
foreach (var user in Model.names)
{
<h5 class="card-title">#user</h5>
}
}
else
{
<h5 class="card-title">None at the moment</h5>
}
</div>
<div class="card-footer">
Add Users
Remove Users
</div>
</div>
</form>
enter code here

Answer 1

I've spent couple of hours looking for an error in my code and the reason for the binder not working in my case was using a model with public fields rather than public properties:
public class EditRoleViewModel
{
public EditRoleViewModel()
{
names = new List<string>();
}
public string Id { get; set; }
[Required]
public string RoleName { get; set; }
public List<string> names { get; set; }
}

Answer 2

The form data you post does not match the property of your model.You do not post the parameter names .
public List names { get; set; }