public ActionResult Edit(GroupEditModel model) { if (ModelState.IsValid) { SubjectManager subjectManager = new SubjectManager(); Group group = subjectManager.GetGroupById(model.GroupId); group.Name = model.GroupName; group.Description = model.Description; long[] users = group.Users.Select(g => g.Id).ToArray(); foreach (long userId in users) { subjectManager.RemoveUserFromGroup(userId, group.Id); } if (Session["Users"] != null) { foreach (GroupMembershipGridRowModel user in (GroupMembershipGridRowModel[]) Session["Users"]) { if (user.IsUserInGroup) { subjectManager.AddUserToGroup(user.Id, group.Id); } } } subjectManager.UpdateGroup(group); return Json(new { success = true }); } else { return PartialView("_EditPartial", model); } }