using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Drawing.Drawing2D; using System.Text; using System.Windows.Forms; public class Form1 : Form { protected override void OnPaint(PaintEventArgs e) { Graphics g = e.Graphics; g.FillRectangle(Brushes.White, this.ClientRectangle); Rectangle rect = new Rectangle(10, 10, 80, 50); g.DrawRectangle(Pens.Black, rect); g.SetClip(rect); g.FillEllipse(Brushes.Blue, 20, 20, 100, 100); } public static void Main() { Application.Run(new Form1()); } }