public ActionResult Update(ApplicationUser _user)
        {
            //The model is valid - update the product and redisplay the grid.
            using (var ctx = new ApplicationDbContext())
            {
                ApplicationUser user = new ApplicationUser();
                user = ctx.Users.Where(x => x.Id == _user.Id).FirstOrDefault();
                if (user != null)
                {
                    user.FirstName = _user.FirstName;
                    user.LastName  = _user.LastName;
                    user.Status    = _user.Status;
                    user.UserRole  = _user.UserRole;
                    user.MobileNo  = _user.MobileNo;
                }
                var    Usermanager      = HttpContext.GetOwinContext().GetUserManager <ApplicationUserManager>();
                string Existinguserrole = string.Empty;
                Existinguserrole = Commonhelper.Rolename(_user.UserRole);
                Usermanager.RemoveFromRole(user.Id, Existinguserrole);
                Usermanager.AddToRole(user.Id, _user.UserRoleName);
                ctx.Entry(user).State = EntityState.Modified;
                ctx.SaveChanges();
            }

            //GridRouteValues() is an extension method which returns the
            //route values defining the grid state - current page, sort expression, filter etc.
            RouteValueDictionary routeValues = this.GridRouteValues();

            return(RedirectToAction("RegisteredAccounts"));
        }