static void Main(string[] args)
{
//何时使用：在不想增加很多子类的情况下扩展类。
RedShapeDecorator decorator = new RedShapeDecorator(new Rectangle());
decorator.Draw();
Console.ReadLine();
}
static void Main(string[] args)
{
IShape circle = new Circle();
Console.WriteLine("Circle with normal border");
circle.Draw();
IShape decoratorCircle = new RedShapeDecorator(new Circle());
Console.WriteLine("\nCircle of red border");
decoratorCircle.Draw();
IShape decoratorRectangle = new RedShapeDecorator(new Rectangle());
decoratorRectangle = new GreenShapeDecorator(decoratorRectangle);
Console.WriteLine("\nRectangle of red border and green background");
decoratorRectangle.Draw();
Console.ReadLine();
}
