public ActionResult AddBrand(string markaAdi)
 {
     if (Session["Admin"] != null)
     {
         bool kontrol = false;
         kontrol = manager.AddBrand(markaAdi);
         if (kontrol)
         {
             return(View("SuccessfullyAddBrand"));
         }
         return(View("FailedAddBrand"));
     }
     else
     {
         return(View("Login"));
     }
 }