public ActionResult ProjectAssign(int Id, List <string> PA) { if (PA == null) { return(new HttpStatusCodeResult(HttpStatusCode.BadRequest)); } var projectHelper = new ProjectHelper(); foreach (var user in db.Users) { projectHelper.RemoveUserToProject(user.Id, Id); } foreach (var userId in PA) { projectHelper.AddUserToProject(userId, Id); } return(RedirectToAction("Index", "Projects")); }