C# seal Functions and Classes

class Shape{// w  w  w  . j ava  2s.c o m
  public virtual int Area{
     get{
        return 0;
     }
  }
}

class Rectangle:Shape{
   public int width;
   public int height;
   
   public sealed override int Area{
      get{
         return width * height;
      }
   }
}