MVC5: UserManager.AddToRole(): “Error Adding User to Role: UserId not found”?

Question

I have been experimenting with MVC5/EF6 and trying out the new Identity Authentication with Code-First Migrations. Everything in the solution is currently building and I can

Answer 1

the issue in my case is that i use (Username) of user instead of Id, working code below:

 public async Task Register(RegisterViewModel model)
        {
            if (ModelState.IsValid)
            {
                var user = new ApplicationUser { UserName = model.Username, Email = model.Username, workshopId =model.workshopId};
                var rolesList = _context.Roles.ToList();
                string role = rolesList.FirstOrDefault(r => r.Id == model.SelectedRoleId).Name;
                var result = await UserManager.CreateAsync(user, model.Password);

                // Add User to the selected role from the list in .cshtml
                if (result.Succeeded)
                {
                    await SignInManager.SignInAsync(user, isPersistent: false, rememberBrowser: false);
                    result =await UserManager.AddToRoleAsync(user.Id, role);
                    // For more information on how to enable account confirmation and password reset please visit https://go.microsoft.com/fwlink/?LinkID=320771
                    // Send an email with this link
                    // string code = await UserManager.GenerateEmailConfirmationTokenAsync(user.Id);
                    // var callbackUrl = Url.Action("ConfirmEmail", "Account", new { userId = user.Id, code = code }, protocol: Request.Url.Scheme);
                    // await UserManager.SendEmailAsync(user.Id, "Confirm your account", "Please confirm your account by clicking here");

                    return RedirectToAction("Index", "Home");
                }
                AddErrors(result);
            }

            // If we got this far, something failed, redisplay form
            return View(model);
        }