2D Graphics C#

using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ComponentModel;
  using System.Windows.Forms;
  using System.Data;
  public class MainForm : System.Windows.Forms.Form
  {
    public MainForm()
    {
      InitializeComponent();
      CenterToScreen();
      SetStyle(ControlStyles.ResizeRedraw, true);  
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "Pens...";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.MainForm_Paint);
    }
    static void Main() 
    {
      Application.Run(new MainForm());
    }
    private void MainForm_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {
      Graphics g = e.Graphics;
      // Draw a pruple dashed polygon as well...
      Pen pen3 = new Pen(Color.Purple, 5);
      pen3.DashStyle = DashStyle.DashDotDot;
      g.DrawPolygon(pen3, new Point[]{new Point(30, 140),
                         new Point(265, 200),
                         new Point(100, 225),
                         new Point(190, 190),
                         new Point(50, 330),
                         new Point(20, 180)} );
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
       Invalidate();  
    }
  }