DropDownListFor报告类型不匹配

Question

Model:

    [Required(ErrorMessage = "You must assign this user a role")]
    [Display(Name = "Role")]
    public string UserRole { get; set; }

    public IEnumerable<System.Web.Mvc.SelectListItem> UserRoles { get; set; }

Controller:

    public ActionResult CreateNewUser()
    {
        CreateNewUserModel model = new CreateNewUserModel();
        model.UserRoles = new []
        {
            new SelectListItem{Value="Administrator", Text="Administrator"},
            new SelectListItem{Value="User", Text="User"}
        };
        //model.UserRole = "Administrator";
        return View(model);
    }

View:

    @Html.DropDownListFor(x => x.UserRole, Model.UserRoles,"Select a role")
    @Html.ValidationMessageFor(x=>x.UserRole)

When the page to create a new user is loaded, I have got an exception stating that UserRole must be of type IEnumerable<SelectList>

Answer 1

Try changing:

model.UserRoles = new []
    {
        new SelectListItem{Value="Administrator", Text="Administrator"},
        new SelectListItem{Value="User", Text="User"}
    };

to:

model.UserRoles = List<SelectListItem>
    {
        new SelectListItem{Value="Administrator", Text="Administrator"},
        new SelectListItem{Value="User", Text="User"}
    };