Question

I use a DropDownList in my MVC application. There is a problem when I load my page: there is a error message shown in the HTML source of the DropDownList.

Please see this image:

This field is already set to allow null in the DB and

using System.Web;
using Nop.Web.Framework;
using Nop.Web.Framework.Mvc;
using Nop.Web.Validators.Customer;

namespace Nop.Web.Models.Customer
{
 public class FileUploadModel : BaseNopEntityModel
 {
    public CustomerNavigationModel NavigationModel { get; set; }
    public string ControlID { get; set; }
    public int? EventID { get; set; }
    public IEnumerable<System.Web.Mvc.SelectListItem> Events { get; set; }
    public string SpeakerFile { get; set; }
    public string FirmFile { get; set; }
    public string LogoFile { get; set; }
    public string PresentFile { get; set; }
    public string Present2File { get; set; }

    public string SpeakerFileUrl { get; set; }
    public string FirmFileUrl { get; set; }
    public string LogoFileUrl { get; set; }
    public string PresentFileUrl { get; set; }
    public string Present2FileUrl { get; set; }

    public string SpeakerSubmit { get; set; }
    public string FirmSubmit { get; set; }
    public string LogoSubmit { get; set; }
    public string PresentSubmit { get; set; }
    public string Present2Submit { get; set; }
 }
}

in model.

Answer 1

Shouldn’t your DropDown list be bound to Events, rather than the EventID?

public int? EventID { get; set; }
public IEnumerable<System.Web.Mvc.SelectListItem> Events { get; set; }