public void ExportLastMonthOrders(String fileName) { LastMonthOrders = new ObservableCollection <Order>(barService.OrdersInCurrentMonth()); string htmlExport = HtmlExporter.ExportToHtml(new Dictionary <string, ICollection <IExportable> >() { { "Orders in last month", new List <IExportable>(LastMonthOrders) } }, "Orders in last month"); File.WriteAllText(fileName, htmlExport); }