Hello,

I am trying to create a QR code from codebehind and save it to the disk without showing it on any GUI.

But it just saves an empty image to the disk, with a size of 169 kb.

Here's the code:

var qrCode = new XamQRCodeBarcode
            {
                Data = data,
                BarsFillMode = BarsFillMode.EnsureEqualSize,
                Stretch = Stretch.None,
                Width = 100,
                Height = 100,
                ErrorCorrectionLevel = QRCodeErrorCorrectionLevel.Medium,
                SizeVersion = SizeVersion.Undefined,
                Fnc1Mode = Fnc1Mode.None,
                EncodingMode = EncodingMode.Undefined,
                EciNumber = 3,
                ApplicationIndicator = ""
            };

            var width = (int)qrCode.Width;
            var height = (int)qrCode.Height;

            var renderTargetBitmap = new RenderTargetBitmap(width, height, 96, 96, PixelFormats.Pbgra32);
            renderTargetBitmap.Render(qrCode);

            var encoder = new PngBitmapEncoder();
            encoder.Frames.Add(BitmapFrame.Create(renderTargetBitmap));

            if (!Directory.Exists(@"C:\Temp\Images\"))
                Directory.CreateDirectory(@"C:\Temp\Images\");
            using (var stream = new FileStream(@"C:\Temp\Images\" + data + ".png", FileMode.Create))
            {
                encoder.Save(stream);
            }

The above code only creates an empty image, then I also tried to use the same code as the infragistic sample without using the XAML, same result empty image.

var saveStream = new SaveFileDialog { Filter = "PNG (*.png) | *.png" };
            var qrCode = new XamQRCodeBarcode
            {
                Data = _page.TxbData.Text,
                BarsFillMode = BarsFillMode.EnsureEqualSize,
                Stretch = Stretch.None,
                Width = 100,
                Height = 100,
                ErrorCorrectionLevel = QRCodeErrorCorrectionLevel.Medium,
                SizeVersion = SizeVersion.Undefined,
                Fnc1Mode = Fnc1Mode.None,
                EncodingMode = EncodingMode.Undefined,
                EciNumber = 3,
                ApplicationIndicator = ""
            };

            var border = new Border
            {
                BorderBrush = Brushes.Red,
                BorderThickness = new Thickness(1),
                Child = qrCode,
                Margin = new Thickness(10)
            };

            _page.StPnlBarcode.Children.Add(border);
            
            var width = (int)qrCode.Width;
            var height = (int)qrCode.Height;

            var renderTargetBitmap = new RenderTargetBitmap(width, height, 96, 96, PixelFormats.Pbgra32);
            renderTargetBitmap.Render(qrCode);

            var encoder = new PngBitmapEncoder();
            encoder.Frames.Add(BitmapFrame.Create(renderTargetBitmap));

           
            if (saveStream.ShowDialog() == false) return;

            using (var stream = saveStream.OpenFile())
            {
                encoder.Save(stream);
            }

The code above creates the QR code and shows in the stackpanel StPnlBarcode, but the image is still empty when saved to disk.