public ListingsViewModel GetItemListingsViewModel(int itemId)
 {
     var httpWebRequest = (HttpWebRequest) WebRequest.Create(GW2ApiItemListings + itemId);
     httpWebRequest.Method = "GET";
     var result = new ListingsViewModel();
     var response = httpWebRequest.GetResponse();
     using (var responseStream = response.GetResponseStream())
     {
         var reader = new StreamReader(responseStream, Encoding.UTF8);
         result = JsonConvert.DeserializeObject<ListingsViewModel>(reader.ReadToEnd());
     }
     return result;
 }
 //ctor populates arrays for buy and sell charts
 public ListingChartViewModel(ListingsViewModel model)
 {
     ItemId = model.id;
     int modelBuysArrayLength = model.buys.Count;
     int modelSellsArrayLength = model.sells.Count;
     BuyListingsInts = new int[modelBuysArrayLength];
     BuyPriceInts = new int[modelBuysArrayLength];
     BuyQuantityInts = new int[modelBuysArrayLength];
     SellListingInts = new int[modelSellsArrayLength];
     SellPriceInts = new int[modelSellsArrayLength];
     SellQuantityInts = new int[modelSellsArrayLength];
     for (int i = 0; i<modelBuysArrayLength; i++)
     {
         BuyListingsInts[i] = model.buys[i].listings;
         BuyPriceInts[i] = model.buys[i].unit_price;
         BuyQuantityInts[i] = model.buys[i].quantity;
     }
     for (int i = 0; i < modelSellsArrayLength; i++)
     {
         SellListingInts[i] = model.sells[i].listings;
         SellPriceInts[i] = model.sells[i].unit_price;
         SellQuantityInts[i] = model.sells[i].quantity;
     }
 }