title: How to delete a drawn circle in c# windows form?
body: <p>I have drawn a circle in windows form</p>
  
  <pre><code>Pen pen = new Pen(Color.Black, 3);
  Graphics gr = this.CreateGraphics();
  gr.DrawEllipse(pen, 5,5,20,20);
  </code></pre>
  
  <p>How to delete it...</p>