async void Print(ITask obj) { tiService.Enabled = false; var rs = CurrentProdLine.GetPrinterStatus(); if (rs != "ready") { return; } var msg = CurrentProdLine.SetPrinterPosition("ContactlessEncoderPosition"); if (msg != "true") { rtbLog.AppendText(String.Format(Texts.SetPrinterPositionError, DateTime.Now.ToString("G"), msg)); rtbLog.AppendText(Environment.NewLine); return; } if (rbDrivingLicense.Checked) { if (!await EncodeDrivingLicense(obj)) { return; } } CurrentProdLine.SetPrinterPosition("PrintPosition"); var frontImage = obj.CreateFrontCard(); var backImage = obj.CreateBackCard(); IEnumerable <Bitmap> pages = new[] { frontImage, backImage }; Print(pages); }