public ActionResult Edit(UsersKnowledgeViewModel collection)
          {
              if (ModelState.IsValid)
              {
                  try
                  {
                      service.Update(collection.ToDALUserKnowl());
                      if (Roles.Provider.IsUserInRole(Membership.GetUser().UserName, "Admin"))
                      {

                          return RedirectToAction("DetailsForAdmin", "Users");
                      }
                      else
                      {
                          return RedirectToAction("Details", "Users", new { id = Membership.GetUser().ProviderUserKey });
                      }
                  }
                  catch
                  {
                      return View("Edit", collection);
                  }
              }
              else
              {
                  return View();
              }
          }
          public ActionResult Create(UsersKnowledgeViewModel mod)
          {
              if (ModelState.IsValid)
              {
                  service.Create(mod.ToDALUserKnowl());
                  if (Roles.Provider.IsUserInRole(Membership.GetUser().UserName, "Admin"))
                  {

                      return RedirectToAction("DetailsForAdmin", "Users");
                  }
                  else
                  {
                      return RedirectToAction("Details", "Users", new { id = Membership.GetUser().ProviderUserKey });
                  }
              }
              else
              {
                  return View("Create", mod);
              }
          }