Drawing inside panel and scrool problem

 private void panel1_Paint(object sender, PaintEventArgs e)
        {
            Graphics g = e.Graphics;
            Pen p1 = new Pen(Color.Black, 5);
            int yL = 40;
            foreach(string ds in Enum.GetNames(typeof(DashStyle)))
            {
                if (ds != "Custom")
                {
                    foreach(string lc in Enum.GetNames(typeof(LineCap))) {
                        p1.DashStyle = (DashStyle)(Enum.Parse(typeof(DashStyle),ds));    
                        p1.StartCap = (LineCap)(Enum.Parse(typeof(LineCap),lc));
                        p1.EndCap = (LineCap)(Enum.Parse(typeof(LineCap), lc));
                        g.DrawLine(p1, 20, yL, 120, yL);
                        g.DrawString("DashStyle:"+ds+"  LineCap:"+lc, new Font("Arial", 10), Brushes.Black, 140, yL-8);
                        yL+=20;
                    }
                }
            }
            p1.Dispose();
        }