public PartialViewResult EditContactClosedFilter(IList<ContactFilter> filters, ContactClosedFilter filter)
        {
            filters.Remove(filters.FirstOrDefault(cf => cf.Id == filter.Id));

            filters.Add(filter);
            return PartialView("DisplayTemplates/contactClosedFilter", filter);
        }
 public PartialViewResult AddContactClosedFilter(IList<ContactFilter> filters)
 {
     var filter = new ContactClosedFilter();
     if(!filters.Any(cf => cf.GetType().Name == filter.GetType().Name))
         filters.Add(filter);
     return PartialView("ContactFilters", filters);
 }