1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Web;
 5 using System.Web.UI;
 6 using System.Web.UI.WebControls;
 7 using System.Drawing;
 8 using System.Drawing.Drawing2D;
 9 
10 public partial class _Default : System.Web.UI.Page
11 {
12     protected void Page_Load(object sender, EventArgs e)
13     {
14         Bitmap bitmap = new Bitmap(240, 200);
15         Graphics g = Graphics.FromImage(bitmap);
16         g.Clear(Color.White);
17         Pen pen = new Pen(Color.Green, 3);
18         Point[] pts = new Point[] { new Point(10, 120), new Point(120, 100), new Point(180, 120), new Point(240, 200), new Point(60, 200) };
19         g.DrawPolygon(pen, pts);
20         System.IO.MemoryStream ms = new System.IO.MemoryStream(); ;
21         bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
22         Response.ClearContent();
23         Response.ContentType = "image/Jpeg";
24         Response.BinaryWrite(ms.ToArray());
25     }
26 }