C#

public class Seat
{
  public virtual void FitSeat()
  {
    // Attach using standard fitments.
  }
}

public class BucketSeat : Seat
{
  public override void FitSeat()
  {
    // Attach using the bucket seat fitments.
  }
}

public class DrawSomething
{
  public class Draw()
  {
    // Do some work....
    OnDraw();
  }
  protected virtual void OnDraw()
  { 
  }
}

public abstract class LayoutManager
{

  public void Save()
  {
    PreSave();
    // Do the actual save work
    PostSave();
  }

  protected abstract void PreSave();
  protected abstract void PostSave();
}

this.comboBox1.AutoCompleteCustomSource.AddRange(new string[] {"summer", "sunshine", "Winter"});
this.comboBox1.AutoCompleteMode = AutoCompleteMode.SuggestAppend;
this.comboBox1.AutoCompleteSource = AutoCompleteSource.CustomSource;