Sending an EMF file to a specific printer / tray in WPF application

Question

I've got a WPF application that needs to send pre-generated EMF files to a specified printer/tray.

I don't want to show the PrintDialog; the actual printer/tray is configured before hand. I also don't need to actually view the EMF file either; but rather just send it to the printer.

So far, all my R&D into this has led to is a bunch of posts that are 5 years old dealing with EMF and WPF and how it isn't supported.

Has anybody had any luck with this before? Can someone point me in the right direction?

Answer 1

Turns out this was easier than I thought. You can do this via a Image control, and use of a converter. This example takes the file location of the emf file, and puts it into a WPF usercontrol that I then send to a printer.

In XAML:

<Grid Margin="12">
    <Image Source="{Binding Path=FileName, Converter={StaticResource emfImageConverter}, Mode=OneWay}"></Image>
</Grid>

and your converter class:

[ValueConversion(typeof(string), typeof(BitmapImage))]
public class EmfImageConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        var fileName = (string)value;
        if (fileName == null || !File.Exists(fileName))
            return new BitmapImage();
        using (var stream = File.Open(fileName, FileMode.Open))
        {
            return GetImage(stream);
        }
    }

    internal BitmapImage GetImage(Stream fileStream)
    {
        var img = Image.FromStream(fileStream);
        var imgBrush = new BitmapImage { CacheOption = BitmapCacheOption.OnLoad, CreateOptions = BitmapCreateOptions.PreservePixelFormat };
        imgBrush.BeginInit();
        imgBrush.StreamSource = ConvertImageToMemoryStream(img);
        imgBrush.EndInit();
        return imgBrush;
    }

    public MemoryStream ConvertImageToMemoryStream(Image img)
    {
        var ms = new MemoryStream();
        img.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
        return ms;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}