Csharp/C Sharp/GUI Windows Form/Popup Menu

Popup Menu action

  using System;
  using System.Drawing;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  public class MainForm : System.Windows.Forms.Form
  {
    private int currFontSize = 20;
    private ContextMenu popUpMenu;
    private MenuItem currentCheckedItem;
    private MenuItem checkedHuge;
    private MenuItem checkedNormal;
    private MenuItem checkedTiny;
    public MainForm()
    {
      InitializeComponent();
      Text = "PopUp Menu";
      CenterToScreen();
      popUpMenu = new ContextMenu();
      popUpMenu.MenuItems.Add("Huge", new EventHandler(PopUp_Clicked));
      popUpMenu.MenuItems.Add("Normal", new EventHandler(PopUp_Clicked));
      popUpMenu.MenuItems.Add("Tiny", new EventHandler(PopUp_Clicked));

      this.ContextMenu = popUpMenu;
      checkedHuge = this.ContextMenu.MenuItems[0];
      checkedNormal = this.ContextMenu.MenuItems[1];        
      checkedTiny = this.ContextMenu.MenuItems[2];
      currentCheckedItem = checkedNormal;
      currentCheckedItem.Checked = true;
      this.Resize += new System.EventHandler(this.MainForm_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.MainForm_Paint);
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "Form1";
    }
    static void Main() 
    {
      Application.Run(new MainForm());
    }
    private void PopUp_Clicked(object sender, EventArgs e) 
    {
      currentCheckedItem.Checked = false;
      MenuItem miClicked = (MenuItem)sender;
      string item = miClicked.Text;
      
      if(item == "Huge")
      {
        currFontSize = 30;
        currentCheckedItem = checkedHuge;
      }
      if(item == "Normal")
      {
        currFontSize = 20;
        currentCheckedItem = checkedNormal;
      }
      if(item == "Tiny")
      {
        currFontSize = 8;
        currentCheckedItem = checkedTiny;
      }
      currentCheckedItem.Checked = true;
      Invalidate();
        }
    private void MainForm_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {
      Graphics g = e.Graphics;
      g.DrawString("Right click your mouse", 
        new Font("Times New Roman", (float)currFontSize), 
        new SolidBrush(Color.Black), 
        this.DisplayRectangle);
    }
    private void MainForm_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }