C# 中的双重调度

双重调度在C#中的应用

csharp
// 定义抽象的图形类
abstract class Shape
{
    public abstract void Draw();
    public void Accept(InteractiveObject interactiveObject)
    {
        interactiveObject.Interact(this);
    }
}
// 定义圆形类
class Circle : Shape
{
    public override void Draw()
    {
        Console.WriteLine("绘制圆形");
    }
}
// 定义矩形类
class Rectangle : Shape
{
    public override void Draw()
    {
        Console.WriteLine("绘制矩形");
    }
}
// 定义抽象的交互对象类
abstract class InteractiveObject
{
    public abstract void Interact(Shape shape);
}
// 定义颜色选择器类
class ColorSelector : InteractiveObject
{
    public override void Interact(Shape shape)
    {
        Console.WriteLine("选择颜色");
        shape.Draw();
    }
}
// 定义画笔类
class Pen : InteractiveObject
{
    public override void Interact(Shape shape)
    {
        Console.WriteLine("使用画笔");
        shape.Draw();
    }
}
// 主程序
class Program
{
    static void Main(string[] args)
    {
        Shape circle = new Circle();
        Shape rectangle = new Rectangle();
        InteractiveObject colorSelector = new ColorSelector();
        InteractiveObject pen = new Pen();
        circle.Accept(colorSelector);
        rectangle.Accept(pen);
    }
}