mvc validationMessage is not working while its in IEnumerable<T> - asp.net-mvc

Question

I have a class :
public class Cust
{
[Required(ErrorMessage ="NameField Req")]
public string Name { get; set; }
}
I use this class :
public class CustModel
{
public IEnumerable<Cust> CustList { get; set; }
}
.Cshtml
#model WebApplication2.Models.CustModel
#Html.EditorFor(m => m.CustList)
#Html.ValidationMessageFor(val => val.CustList)
When I hit on Submit button if (ModelState.IsValid){} is working but why my error message is not displayed ?

Answer 1

I managed to re-produce your code, assuming your view:
Please, pay attention to the for loop:
#model MVC_SteckOverflow.Models.ViewModels.CustModel
#using MVC_SteckOverflow.Models.ViewModels
#{
ViewBag.Title = "ValidateIenumerable";
}
<style>
.field-validation-error {
color:#F00;
}
.input-validation-error {
border: 1px solid red;
background-color: #f9e2e2b3;
}
</style>
<h2>ValidateIenumerable</h2>
#using (Html.BeginForm())
{
#Html.AntiForgeryToken()
<div class="form-horizontal">
<h4>CustModel</h4>
<hr />
#Html.ValidationSummary(true, "", new { #class = "text-danger" })
<div class="form-group">
#for (int i = 0; i != Model.CustList.Count(); i++)
{
#Html.EditorFor(x => x.CustList.ToList()[i].Name)
#Html.ValidationMessageFor(x => x.CustList.ToList()[i].Name)
}
<div class="col-md-offset-2 col-md-10">
<input type="submit" value="Create" class="btn btn-default" />
</div>
</div>
</div>
}
<div>
#Html.ActionLink("Back to List", "Index")
</div>
#section scripts{
#Scripts.Render("~/bundles/jqueryval")
}
according to the following actions in the Controller:
public ActionResult ValidateIenumerable()
{
CustModel custModel = new CustModel {
CustList = new List<Cust> {
new Cust{ Name = "A"},
new Cust{ Name = "B"},
new Cust{ Name = "C"},
},
};
return View(custModel);
}
[HttpPost]
public ActionResult ValidateIenumerable(CustModel custModel)
{
return View(custModel);
}
The code above, is tested, built and run successfully.
Hope this helped ... :)