Graphics: SetClip

   
 
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;
   
class KeyholeClip: Form
{
     protected Image        image;
     protected GraphicsPath path;
   
     public static void Main()
     {
          Application.Run(new KeyholeClip());
     }
     public KeyholeClip()
     {
          ResizeRedraw = true;
          image = Image.FromFile("Color.jpg");
   
          path = new GraphicsPath();
          path.AddArc(80, 0, 80, 80, 45, -270);
          path.AddLine(70, 180, 170, 180);
     }
     protected override void OnPaint(PaintEventArgs pea)
     {
          pea.Graphics.SetClip(path);
          pea.Graphics.DrawImage(image, 0, 0, image.Width, image.Height);
     }      

}