Graphics from windows forms to Silverlight?

Question

The following code works for windows forms. How can I do this to Silverlight? I guess there is no graphics object.


Bitmap bm = new Bitmap(600, 600);
Graphics g = Graphics.FromImage(bm);
Brush b = new LinearGradientBrush(
new Point(1, 1), new Point(600, 600),
Color.White, Color.Red);
Point[] points = new Point[]
{new Point(10, 10),
 new Point(77, 500),
 new Point(590, 100),
 new Point(250, 590),
 new Point(300, 410)};
 g.FillPolygon(b, points);
 bm.Save("testandoImagem.jpg", ImageFormat.Jpeg);

score 2 · Answer 1 · answered Mar 04 '11 at 16:45

Alan, even from a SL client application you can do this all server side, you are not showing anything in the User Interface, I would put this code in the business layer which has full access to the .NET Framework. Keep in mind that from SL you can't save on the client machine directly so you should use another way.

score 1 · Answer 2 · edited May 23 '17 at 12:04

You could render the shape as a WriteableBitmap, but Silverlight does not have built in support for encoding the data to JPEG.

See these StackOverflow questions:

How to save BitmapImage / WriteableBitmap using SaveFileDialog in Silverlight 3.0?

Best Jpeg Encoder for Silverlight 4.0

http://msdn.microsoft.com/en-us/library/system.windows.media.imaging.writeablebitmap.render(v=VS.95).aspx

        WriteableBitmap wb = new WriteableBitmap(600, 600);
        Polygon p = new Polygon();
        p.Points = new PointCollection() { new Point(10, 10), new Point(77, 500), new Point(590, 100), new Point(250, 590), new Point(300, 410) };
        p.Fill = new LinearGradientBrush()
        {
            //Gradient angle is 0,0 to 1,1 by default
            GradientStops = new GradientStopCollection() { 
                new GradientStop() { Color = Colors.White, Offset = 0 }, 
                new GradientStop() { Color = Colors.Red, Offset = 1 } }
        };

        wb.Render(p, null);
        wb.Invalidate();

        //Save WriteableBitmap as described in other questions

Graphics from windows forms to Silverlight?

2 Answers2