import namespaces 

using System.Drawing;
using System.Drawing.Imaging;

Add This Code In PageLoad


 protected void Page_Load(object sender, EventArgs e)
    {
        int width = 200;
        int height = 200;
        int iterations = 10000;
        //create instance for bitmap class
        Bitmap bitmap = new Bitmap(width, height);
        // Create our triangle's three Points
        Point top = new Point(width / 2, 0),bottomLeft = new Point(0, height), bottomRight = new Point(width, height);
        // Now, choose our starting point
        Point current = new Point(width / 2, height / 2);
        // Iterate iterations times
        Random rnd = new Random();
        for (int iLoop = 0; iLoop < iterations; iLoop++)
        {
            // draw the pixel
            bitmap.SetPixel(current.X, current.Y, Color.Red);

            // Choose our next pixel
            switch (rnd.Next(3))
            {
                case 0:
                    current.X -= (current.X - top.X) / 2;
                    current.Y -= (current.Y - top.Y) / 2;
                    break;

                case 1:
                    current.X -= (current.X - bottomLeft.X) / 2;
                    current.Y -= (current.Y - bottomLeft.Y) / 2;
                    break;

                case 2:
                    current.X -= (current.X - bottomRight.X) / 2;
                    current.Y -= (current.Y - bottomRight.Y) / 2;
                    break;
            }
        }
        bitmap.Save(@"D:\img", ImageFormat.Gif); 

        // Save the image to the OutputStream
        Response.ContentType = "image/jpeg";
        bitmap.Save(Response.OutputStream, ImageFormat.Jpeg);

        // clean up...
        bitmap.Dispose();

    }