using System; using System.Drawing; using System.Drawing.Imaging; using System.Drawing.Drawing2D; using System.Collections; using System.ComponentModel; using System.Windows.Forms; using System.Data; public class TestGDI4 : System.Windows.Forms.Form{ //in order to paint something OnPaint method needs to be overridden protected override void OnPaint(System.Windows.Forms.PaintEventArgs pe) { //OnPaint method is a member of Form class //The following call sends pe to an event listener Graphics base.OnPaint(pe); Graphics g = pe.Graphics ; Pen pn = new Pen( Color.Blue, 100 ); Rectangle rect = new Rectangle(50, 50, 200, 100); g.DrawEllipse( pn, rect ); } public static void Main() { System.Windows.Forms.Application.Run(new TestGDI4());//display form } }