public JsonResult EditTask(ActivityTask task, List<int> AcSeleUserIds)
 {
     ModelState.Clear();
     if ((AcSeleUserIds == null || AcSeleUserIds.Count == 0) && task.UserId == 0)
     {
         ModelState.AddModelError("", "Add Responsible Person");
     }
     else
     {
         var userId = AcSeleUserIds != null && AcSeleUserIds.Count > 0 ? AcSeleUserIds[0] : task.UserId;
         var user = _db.Users.Find(userId);
         task.UserName = user.FullName;
         task.UserId = user.UserId;
         if (task.IsNew)
         {
             _db.Entry(task).State = System.Data.EntityState.Added;
         }
         else
         {
             _db.Entry(task).State = System.Data.EntityState.Modified;
         }
         _db.SaveChanges();
     }
     return GetErrorMsgJSON();
 }
 public PartialViewResult AddTask(int id)
 {
     var activity = new ActivityTask
     {
         ActivityId = id
     };
     ViewBag.Status = activity.Status.ToSelectList();
     return PartialView("EditTask", activity);
 }