Hi All, I'm trying to implement my own surface controller to handle member registration with an extra field called IsValidated

I'm in PureLive mode

I've tried to follow a number of tutorials, including these: https://our.umbraco.com/documentation/reference/templating/modelsbuilder/Understand-And-Extend https://24days.in/umbraco-cms/2016/getting-started-with-modelsbuilder/ https://our.umbraco.com/Documentation/Reference/Templating/Mvc/Forms/tutorial-child-action

I've tried to extend RegisterModel with a file in ~Models/Membership/RegisterModel.cs

   using System;
using System.ComponentModel.DataAnnotations;
using Umbraco.Web.Models;



//Needs to be in same namespace to extend
//https://our.umbraco.com/forum/templates-partial-views-and-macros/80378-extend-model-using-partial-class#comment-288095
namespace Umbraco.Web.Models
{ 
    public partial class RegisterModel
    {

        /// <summary>
        /// Is member's email validated
        /// </summary>
        public Boolean IsValidated { get; set; }
    }
}

And have just copied the umbRegisterController from the umbraco source code, adding my own ChildAction to render the form ~Controllers/CustomerMembershipController.cs

using System;
using System.Web.Mvc;
using System.Web.Security;
using Umbraco.Core;
using Umbraco.Core.Cache;
using Umbraco.Core.Logging;
using Umbraco.Core.Persistence;
using Umbraco.Core.Services;
using Umbraco.Web.Models;
using Umbraco.Web.Mvc;


    public class CustomerMembershipController : SurfaceController
    {
        public CustomerMembershipController()
        {
        }

        [HttpPost]
        [ValidateAntiForgeryToken]
        [ValidateUmbracoFormRouteString]
        public ActionResult Register([Bind(Prefix = "registerModel")] RegisterModel model)
        {
            if (ModelState.IsValid == false)
            {
                return CurrentUmbracoPage();
            }

            // U4-10762 Server error with "Register Member" snippet (Cannot save member with empty name)
            // If name field is empty, add the email address instead
            if (string.IsNullOrEmpty(model.Name) && string.IsNullOrEmpty(model.Email) == false)
            {
                model.Name = model.Email;
            }

            var test = model.IsValidated;

            MembershipCreateStatus status;
            var member = Members.RegisterMember(model, out status, model.LoginOnSuccess);

            switch (status)
            {
                case MembershipCreateStatus.Success:

                    TempData["FormSuccess"] = true;

                    //if there is a specified path to redirect to then use it
                    if (model.RedirectUrl.IsNullOrWhiteSpace() == false)
                    {
                        return Redirect(model.RedirectUrl);
                    }
                    //redirect to current page by default

                    return RedirectToCurrentUmbracoPage();
                case MembershipCreateStatus.InvalidUserName:
                    ModelState.AddModelError((model.UsernameIsEmail || model.Username == null)
                        ? "registerModel.Email"
                        : "registerModel.Username",
                        "Username is not valid");
                    break;
                case MembershipCreateStatus.InvalidPassword:
                    ModelState.AddModelError("registerModel.Password", "The password is not strong enough");
                    break;
                case MembershipCreateStatus.InvalidQuestion:
                case MembershipCreateStatus.InvalidAnswer:
                    // TODO: Support q/a http://issues.umbraco.org/issue/U4-3213
                    throw new NotImplementedException(status.ToString());
                case MembershipCreateStatus.InvalidEmail:
                    ModelState.AddModelError("registerModel.Email", "Email is invalid");
                    break;
                case MembershipCreateStatus.DuplicateUserName:
                    ModelState.AddModelError((model.UsernameIsEmail || model.Username == null)
                        ? "registerModel.Email"
                        : "registerModel.Username",
                        "A member with this username already exists.");
                    break;
                case MembershipCreateStatus.DuplicateEmail:
                    ModelState.AddModelError("registerModel.Email", "A member with this e-mail address already exists");
                    break;
                case MembershipCreateStatus.UserRejected:
                case MembershipCreateStatus.InvalidProviderUserKey:
                case MembershipCreateStatus.DuplicateProviderUserKey:
                case MembershipCreateStatus.ProviderError:
                    //don't add a field level error, just model level
                    ModelState.AddModelError("registerModel", "An error occurred creating the member: " + status);
                    break;
                default:
                    throw new ArgumentOutOfRangeException();
            }

            return CurrentUmbracoPage();
        }

        [ChildActionOnly]
        public ActionResult ShowCommentForm()
        {
            return PartialView("RegisterForm");
        }

    }

With this, the RegisterModel I created seems to override the default one generated by Umbraco, so Visual studio shows that model.IsValidated is available, but the rest of the default fields are not.

Any ideas please?