public IActionResult SubmitJunk(string name, string details, string phone) { Junk junk = new Junk { Name = name, Details = details, Phone = phone }; DbManager db = new DbManager(_connectionString); int newId = db.AddJunk(junk); if (HttpContext.Session.Get <List <int> >("ListOfIds") == null) { List <int> idList = new List <int>(); HttpContext.Session.Set("ListOfIds", idList); } List <int> idListToAddTo = HttpContext.Session.Get <List <int> >("ListOfIds"); idListToAddTo.Add(newId); HttpContext.Session.Set("ListOfIds", idListToAddTo); return(Redirect($"/home/index")); }