// Encrypt the receipts and save them to file.
 void ToCache(IList<Receipt> receipts)
 {
     OuyaFacade.Log("Caching receipts");
     var json = new JSONObject();
     var array = new JSONArray();
     foreach (var receipt in receipts)
     {
         var r = new JSONObject();
         r.Put("identifier", receipt.Identifier);
         r.Put("priceInCents", receipt.PriceInCents);
         r.Put("purchaseDate", receipt.PurchaseDate.ToGMTString());
         r.Put("generatedDate", receipt.GeneratedDate.ToGMTString());
         r.Put("gamerUuid", receipt.Gamer);
         r.Put("uuid", receipt.Uuid);
         array.Put(r);
     }
     json.Accumulate("receipts", array);
     var text = json.ToString();
     var encryptedReceipts = CryptoHelper.Encrypt(text, _gamerUuid);
     using (var store = IsolatedStorageFile.GetUserStoreForApplication())
     {
         using (var writer = new StreamWriter(store.OpenFile(receiptsFileName, FileMode.OpenOrCreate)))
         {
             writer.Write(encryptedReceipts);
         }
     }
 }
 // Encrypt the receipts and save them to file.
 static void ToCache(IList<Receipt> receipts, string gamerUuid)
 {
     OuyaFacade.Log("Caching receipts");
     var json = new JSONObject();
     var array = new JSONArray();
     foreach (var receipt in receipts)
     {
         var r = new JSONObject();
         r.Put("identifier", receipt.Identifier);
         // PriceInCents is now deprecated. Use LocalPrice and CurrencyCode instead.
         // Retain field for compatibility.
         r.Put("priceInCents", 0);
         r.Put("purchaseDate", receipt.PurchaseDate.ToGMTString());
         r.Put("generatedDate", receipt.GeneratedDate.ToGMTString());
         r.Put("gamerUuid", receipt.Gamer);
         r.Put("uuid", receipt.Uuid);
         r.Put("localPrice", receipt.LocalPrice);
         r.Put("currencyCode", receipt.Currency);
         array.Put(r);
     }
     json.Accumulate("receipts", array);
     var text = json.ToString();
     var encryptedReceipts = CryptoHelper.Encrypt(text, gamerUuid);
     using (var store = IsolatedStorageFile.GetUserStoreForApplication())
     {
         using (var writer = new StreamWriter(store.OpenFile(receiptsFileName, FileMode.OpenOrCreate)))
         {
             writer.Write(encryptedReceipts);
         }
     }
 }