Question

private void Draw(){
     int width  = Screen.PrimaryScreen.Bounds.Width;
     int height = Screen.PrimaryScreen.Bounds.Height;
     Bitmap image= new Bitmap(width, height);
     Graphics gr =  Graphics.FromImage(image);
     gr.CopyFromScreen(0, 0, 0, 0, new Size(width, height));
     Random rnd = new Random();

     gr.DrawEllipse(new Pen(Color.Red, rnd.Next(100)), rnd.Next(300), rnd.Next(100), rnd.Next(600), rnd.Next(1000));
     Point[] p = new Point[3];
     p[0] = new Point(rnd.Next(30),  rnd.Next(60));
     p[1] = new Point(rnd.Next(100), rnd.Next(260));
     p[2] = new Point(rnd.Next(30),  rnd.Next(10));
     gr.DrawPolygon(Pens.AliceBlue, p);
     gr.DrawBeziers(Pens.Yellow, p);
     pcImageBox.Image = image;
}

When I use Timer and call the Draw() method every 300 milliseconds everything works fine, but when I look into process manager, my project uses more memory (memory increases every 300 milliseconds)

Maybe I should use garbage collector or use p = null; etc. How can I resolve this problem?

Thank you for help and sorry for my bad english..

Answer 1

You never disposed your Graphics object.

Use using, like:

using (Graphics gr =  Graphics.FromImage(image)) {
     ...
}
pcImageBox.Image = image;

Also, don’t create a brand new Bitmap every frame. Save the old one in a member variable, and draw over it during the next call. Only make a new one if the screen size changes (Screen.PrimaryScreen.Bounds != image.Size).