C#

class ZipHolder
{
   private ZipHolder()
   {
   }

   private ZipArchive zip = null;

   public ZipHolder Instance = new ZipHolder();

   public void Open(string name)
   {
     zip = new ZipArchive(name);
     ....
   }

   public ZipArchive Zip
   {
       get { return zip; }
   }
}

public void ShowImage(int theNum)
{
    AbstractFile imageFile = ZipHolder.Instance.Zip.GetFile(zipFiles[num]);
    if (imageFile.Exists)
    {
        using( Stream stImage = imageFile.OpenRead() )
        {
             pbMain.Image = Image.FromStream(stImage);
        }
    }
}

using (FileStream stream = new FileStream(filename, FileMode.OpenOrCreate, FileAccess.Write))
{
  using (StreamWriter swr = new StreamWriter(stream))
  {
    swr.WriteLine(this.Title); // etc.
    swr.Flush();
  }
}

if (System.DateTime.Now.Equals(shut.getDateTime()))
this.Computer_Shutdown();

Timer shutTimer = new Timer();
shutTimer.Tick += new EventHandler(shutTimer_Tick);
TimeSpan waitDuration = shut.GetDateTime().Subtract(DateTime.Now);
shutTimer.Interval = (int)waitDuration.TotalMilliseconds;
shutTimer.Start();
[...].private void shutTimer_Tick(object sender, EventArgs e)
{
  this.Computer_Shutdown();
}