public ActionResult BLR020_Invoice(string invoiceNo)
        {
            try
            {
                IBillingDocumentHandler handlerBillingDocument = ServiceContainer.GetService <IBillingDocumentHandler>() as IBillingDocumentHandler;

                // Mothed #2: Official generate
                Stream stream2 = handlerBillingDocument.GenerateBLR020(invoiceNo, CommonUtil.dsTransData.dtUserData.EmpNo, DateTime.Now);

                return(File(stream2, "application/pdf"));
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }