c# - Static member being removed in HttpPost -

in asp.netcore mvc controller adding new object (restaurant) static list _restaurantdata httppost create method below, , redirecting "details" page of new restaurant. while debugging, can verify new restaurant added _restaurantdata correct properites , correct id passed redirecttoaction method. once 'details' called though, new restaurant object has been removed _restaurantdata , 'model' null. how new restaurant possibly removed list between "create"'s return statement , beginning of "details"? , how fix this!

[httppost]     public iactionresult create(restuaranteditviewmodel model)     {         var restaurant = new restaurant();         restaurant.name = model.name;         restaurant.cuisine = model.cuisine;          _restaurantdata.add(restaurant);          return redirecttoaction("details", new { id = restaurant.id });     }      public iactionresult details(int id)     {         var model = _restaurantdata.get(id);         if (model == null)         {             return redirecttoaction("index");         }         return view(model);     } 

here code add restaurant list.

public void add(restaurant newrestaurant)     {         newrestaurant.id = _restaurants.max(r => r.id) + 1;         _restaurants.add(newrestaurant);     } 

when redirect, state of page (and underlying controller class), lost, including static variables. need save after have added new instance:

_restaurantdata.add(restaurant); _restaurantdata.savechanges(); // assuming dbcontext 

then, when page loads on details page, database have model saved , retrieve it.

if _restaurantdata not dbcontext, need have way save data between page loads.