public virtual async Task<ActionResult> Register(RegisterViewModel model)
        {
            try
            {
                CheckModelState();

                //Get tenancy name and tenant
                if (!_multiTenancyConfig.IsEnabled)
                {
                    model.TenancyName = Tenant.DefaultTenantName;
                }
                else if (model.TenancyName.IsNullOrEmpty())
                {
                    throw new UserFriendlyException(L("TenantNameCanNotBeEmpty"));
                }

                var tenant = await GetActiveTenantAsync(model.TenancyName);

                //Create user
                var user = new User
                {
                    TenantId = tenant.Id,
                    Name = model.Name,
                    Surname = model.Surname,
                    EmailAddress = model.EmailAddress,
                    IsActive = true
                };

                //Get external login info if possible
                ExternalLoginInfo externalLoginInfo = null;
                if (model.IsExternalLogin)
                {
                    externalLoginInfo = await AuthenticationManager.GetExternalLoginInfoAsync();
                    if (externalLoginInfo == null)
                    {
                        throw new ApplicationException("Can not external login!");
                    }

                    user.Logins = new List<UserLogin>
                    {
                        new UserLogin
                        {
                            LoginProvider = externalLoginInfo.Login.LoginProvider,
                            ProviderKey = externalLoginInfo.Login.ProviderKey
                        }
                    };

                    model.UserName = model.EmailAddress;
                    model.Password = Users.User.CreateRandomPassword();

                    if (string.Equals(externalLoginInfo.Email, model.EmailAddress, StringComparison.InvariantCultureIgnoreCase))
                    {
                        user.IsEmailConfirmed = true;
                    }
                }
                else
                {
                    //Username and Password are required if not external login
                    if (model.UserName.IsNullOrEmpty() || model.Password.IsNullOrEmpty())
                    {
                        throw new UserFriendlyException(L("FormIsNotValidMessage"));
                    }
                }

                user.UserName = model.UserName;
                user.Password = new PasswordHasher().HashPassword(model.Password);

                //Switch to the tenant
                _unitOfWorkManager.Current.EnableFilter(AbpDataFilters.MayHaveTenant);
                _unitOfWorkManager.Current.SetFilterParameter(AbpDataFilters.MayHaveTenant, AbpDataFilters.Parameters.TenantId, tenant.Id);

                //Add default roles
                user.Roles = new List<UserRole>();
                foreach (var defaultRole in await _roleManager.Roles.Where(r => r.IsDefault).ToListAsync())
                {
                    user.Roles.Add(new UserRole { RoleId = defaultRole.Id });
                }

                //Save user
                CheckErrors(await _userManager.CreateAsync(user));
                await _unitOfWorkManager.Current.SaveChangesAsync();

                //Directly login if possible
                if (user.IsActive)
                {
                    AbpUserManager<Tenant, Role, User>.AbpLoginResult loginResult;
                    if (externalLoginInfo != null)
                    {
                        loginResult = await _userManager.LoginAsync(externalLoginInfo.Login, tenant.TenancyName);
                    }
                    else
                    {
                        loginResult = await GetLoginResultAsync(user.UserName, model.Password, tenant.TenancyName);
                    }

                    if (loginResult.Result == AbpLoginResultType.Success)
                    {
                        await SignInAsync(loginResult.User, loginResult.Identity);
                        return Redirect(Url.Action("Index", "Home"));
                    }

                    Logger.Warn("New registered user could not be login. This should not be normally. login result: " + loginResult.Result);
                }

                //If can not login, show a register result page
                return View("RegisterResult", new RegisterResultViewModel
                {
                    TenancyName = tenant.TenancyName,
                    NameAndSurname = user.Name + " " + user.Surname,
                    UserName = user.UserName,
                    EmailAddress = user.EmailAddress,
                    IsActive = user.IsActive,
                    IsEmailConfirmationRequired = false
                });
            }
            catch (UserFriendlyException ex)
            {
                ViewBag.IsMultiTenancyEnabled = _multiTenancyConfig.IsEnabled;
                ViewBag.ErrorMessage = ex.Message;

                return View("Register", model);
            }
        }
        private async Task<ActionResult> RegisterView(ExternalLoginInfo loginInfo, string tenancyName = null)
        {
            var name = loginInfo.DefaultUserName;
            var surname = loginInfo.DefaultUserName;

            var extractedNameAndSurname = TryExtractNameAndSurnameFromClaims(loginInfo.ExternalIdentity.Claims.ToList(), ref name, ref surname);

            var viewModel = new RegisterViewModel
            {
                TenancyName = tenancyName,
                EmailAddress = loginInfo.Email,
                Name = name,
                Surname = surname,
                IsExternalLogin = true
            };

            if (!tenancyName.IsNullOrEmpty() && extractedNameAndSurname)
            {
                return await Register(viewModel);
            }

            return RegisterView(viewModel);
        }
        private ActionResult RegisterView(RegisterViewModel model)
        {
            ViewBag.IsMultiTenancyEnabled = _multiTenancyConfig.IsEnabled;

            return View("Register", model);
        }