validation failing on dropdown MVC - validation

Question

I am using code-first with EF. Validation seems to be failing on a dropdown list with the error System.NullReferenceException: Object reference not set to an instance of an object. This happens when I save a record and I intentionally leave controls empty to test the validation. It happens even if the dropdown list itself has a selection.
here is part of my view:
<div class="editor">
#Html.LabelFor(model => model.EmployeeID)
#Html.DropDownListFor(model => model.EmployeeID, new SelectList(Model.Employees, "Value", "Text"))
#Html.ValidationMessageFor(model => model.EmployeeID)
</div>
If I use a textbox validation works:
<div class="editor">
#Html.LabelFor(model => model.EmployeeID)
#Html.TextBoxFor(model => model.EmployeeID, new { style = "width: 250px;" })
#Html.ValidationMessageFor(model => model.EmployeeID)
</div>
here are my Create controller actions:
public ActionResult Create()
{
var e = iEmployeeRepository.GetAll();
var visitorLogViewModel = new VisitorLogViewModel
{
Employees = e.Select(x => new SelectListItem
{
Value = x.EmployeeID,
Text = x.EmployeeName
})
};
return View(visitorLogViewModel);
}
//
// POST: /VisitorLogs/Create
[HttpPost]
public ActionResult Create(VisitorLog visitorlog)
{
if (ModelState.IsValid) {
iVisitorlogRepository.Add(visitorlog);
iVisitorlogRepository.Save();
return RedirectToAction("Search");
} else {
return View();
}
}
And my viewmodel:
public class VisitorLogViewModel
{
public int Id { get; set; }
[Display(Name = "Visitor Name")]
public string VisitorName { get; set; }
[Display(Name = "Company Name")]
public string CompanyName { get; set; }
[Required(ErrorMessage = "Employee ID is required.")]
[Display(Name = "GB Employee")]
public string EmployeeID { get; set; }
[Display(Name = "Visit Reason")]
public string VisitReason { get; set; }
[Display(Name = "Time In")]
public DateTime TimeIn { get; set; }
[Display(Name = "Time Out")]
public DateTime TimeOut { get; set; }
[Display(Name = "GB Employee")]
public string EmployeeName { get; set; }
public IEnumerable Employees { get; set; }
public VisitorLog VisitorLog { get; set; }
}
And my partial model for validation:
[MetadataType(typeof(VisitorLogMetaData))]
public partial class VisitorLog
{
}
public class VisitorLogMetaData
{
[Required(ErrorMessage = "Visitor name is required.")]
[MaxLength(128)]
public string VisitorName { get; set; }
[Required(ErrorMessage = "Company name is required.")]
[MaxLength(128)]
public string CompanyName { get; set; }
[Required(ErrorMessage = "GB Employee is required.")]
[MaxLength(128)]
public string EmployeeID { get; set; }
[Required(ErrorMessage = "Visit reason is required.")]
[MaxLength(254)]
public string VisitReason { get; set; }
[Required(ErrorMessage = "Time in is required.")]
public DateTime TimeIn { get; set; }
[Required(ErrorMessage = "Time out reason is required.")]
public DateTime TimeOut { get; set; }
}
And finally my model:
public partial class VisitorLog
{
public int Id { get; set; }
public string VisitorName { get; set; }
public DateTime TimeIn { get; set; }
public DateTime TimeOut { get; set; }
public string CompanyName { get; set; }
public string EmployeeID { get; set; }
public string VisitReason { get; set; }
// Navigation properties
[ForeignKey("EmployeeID")]
public virtual Employee Employee { get; set; }
}
I read there was a bug in MVC razor regarding the DropDownListFor but I don't know if that applies in my situation. I have tried some of the solutions and they didn't work for me. I am using 4.5 framework.
Thanks.
Edit:
One thing I noticed, when I submit the page and the error stops on the dropdown element:
#Html.DropDownListFor(model => model.EmployeeID, new SelectList(Model.Employees, "Value", "Text"))
the Model in Model.Employees is null, like it is loosing its binding when the page is submited.

Answer 1

Ok, I did some fundemental changes to my classes. First, I changed the post method in my controller. Previously I was passing the model to the post, now I am passing the view model and mapping it to the model before saving via my repository:
//
// POST: /VisitorLogs/Create
[HttpPost]
public ActionResult Create(VisitorLogViewModel visitorLogViewModel)
{
var e = iEmployeeRepository.GetAll();
VisitorLog visitorLog = new VisitorLog();
visitorLog.Id = visitorLogViewModel.Id;
visitorLog.VisitorName = visitorLogViewModel.VisitorName;
visitorLog.CompanyName = visitorLogViewModel.CompanyName;
visitorLog.EmployeeID = visitorLogViewModel.EmployeeID;
visitorLog.TimeIn = visitorLogViewModel.TimeIn;
visitorLog.TimeOut = visitorLogViewModel.TimeOut;
visitorLog.VisitReason = visitorLogViewModel.VisitReason;
visitorLogViewModel.Employees = new SelectList(e, "EmployeeID", "EmployeeName");
if (ModelState.IsValid)
{
iVisitorlogRepository.Add(visitorLog);
iVisitorlogRepository.Save();
return RedirectToAction("Search");
} else {
return View(visitorLogViewModel);
}
}
Next, I had to add the "required" attribute (validation) to the viewmodel:
public class VisitorLogViewModel
{
public int Id { get; set; }
[Required(ErrorMessage = "Visitor name is required.")]
[MaxLength(128)]
[Display(Name = "Visitor Name")]
public string VisitorName { get; set; }
[Required(ErrorMessage = "Company name is required.")]
[MaxLength(128)]
[Display(Name = "Company Name")]
public string CompanyName { get; set; }
[Required(ErrorMessage = "GB Employee is required.")]
[MaxLength(16)]
[Display(Name = "GB Employee")]
public string EmployeeID { get; set; }
[Required(ErrorMessage = "Visit Reason is required.")]
[MaxLength(254)]
[Display(Name = "Visit Reason")]
public string VisitReason { get; set; }
[Display(Name = "Time In")]
public DateTime TimeIn { get; set; }
[Display(Name = "Time Out")]
public DateTime TimeOut { get; set; }
[Display(Name = "GB Employee")]
public string EmployeeName { get; set; }
public SelectList Employees { get; set; }
}
Not sure if that is the most effcient method but everything works now. If someone sees something wrong with this method let me know.