Easiest way of saving wpf Image control to a file

Question

I have a Image control inside my wpf application, which has a large image inside of it, but the control itself is only 60x150, this means it only shows a certain portion of

Answer 1

You could use RenderTargetBitmap class and BitmapEncoder.

Define these methods:

void SaveToBmp(FrameworkElement visual, string fileName)
{
    var encoder = new BmpBitmapEncoder();
    SaveUsingEncoder(visual, fileName, encoder);
}

void SaveToPng(FrameworkElement visual, string fileName)
{
    var encoder = new PngBitmapEncoder();
    SaveUsingEncoder(visual, fileName, encoder);
}

// and so on for other encoders (if you want)


void SaveUsingEncoder(FrameworkElement visual, string fileName, BitmapEncoder encoder)
{
    RenderTargetBitmap bitmap = new RenderTargetBitmap((int)visual.ActualWidth, (int)visual.ActualHeight, 96, 96, PixelFormats.Pbgra32);
    bitmap.Render(visual);
    BitmapFrame frame = BitmapFrame.Create(bitmap);
    encoder.Frames.Add(frame);

    using (var stream = File.Create(fileName))
    {
        encoder.Save(stream);
    }
}

If you have your Image control inside a container like this:

You just need to do so:

SaveToPng(MyGrid, "image.png");

Otherwise you can simply pass the dimensions you want when you use RenderTargetBitmap:

SaveToPng(MyImage, "image.png");

...

RenderTargetBitmap bitmap = new RenderTargetBitmap(YourWidth, YourHeight, 96, 96, PixelFormats.Pbgra32);