using System;
using System.Drawing;
using System.Windows.Forms;
 
class App{
   public static void Main(){
      Application.Run(new ViewForm());
   }
}
 
class ViewForm:Form{  
   public ViewForm(){      
      MenuItem file = new MenuItem("&File");
      file.MenuItems.Add("Open", new EventHandler(OnOpen));
      file.MenuItems.Add("-");
      file.MenuItems.Add("Exit", new EventHandler(OnExit));            
      this.Menu = new MainMenu(new MenuItem[]{file});
      this.Text = "MDI Image Viewer";
      this.IsMdiContainer = true;      
   }   
   
   void OnOpen(Object sender, EventArgs args){
      OpenFileDialog ofd = new OpenFileDialog();
      ofd.Filter = "Image Files (JPEG, GIF, BMP, etc.)|" +
         "*.jpg;*.jpeg;*.gif;*.bmp;*.tif;*.tiff;*.png|" +         
         "All files (*.*)|*.*";
      
      if (ofd.ShowDialog() == DialogResult.OK) {
         String fileName = ofd.FileName;
         if (fileName.Length != 0) {            
            try {
               Form bitmap = new BitmapForm(fileName, this);               
            }catch(ArgumentException e) {                              
               MessageBox.Show(String.Format(
                  "{0} is not a valid image file", fileName));
            }
         }
      }      
   }
 
   void OnExit(Object sender, EventArgs args){
      this.Close();
   }
}
 
class BitmapForm:Form{
   Bitmap bitmap;
   public BitmapForm(String filename, Form parent){      
      bitmap = new Bitmap(filename);
      if(parent != null){
         this.MdiParent = parent;
      }
      this.ResizeRedraw = true;
      this.Text = filename;
      this.Show();
   }
 
   protected override void OnPaint(PaintEventArgs args){
      base.OnPaint(args);
      args.Graphics.DrawImage(bitmap, this.ClientRectangle);
   }
}