class1.cs

来自DoFactory的设计模式, 由于是本人根据已有代码创建,没有NETOptimized项

// Chain of Responsibility pattern -- Real World example  

using System;

namespace DoFactory.GangOfFour.Chain.RealWorld
{

    // MainApp test application 

    class MainApp
    {
        static void Main()
        {
            // Setup Chain of Responsibility 
            Director Larry = new Director();
            VicePresident Sam = new VicePresident();
            President Tammy = new President();
            Larry.SetSuccessor(Sam);
            Sam.SetSuccessor(Tammy);

            // Generate and process purchase requests 
            Purchase p = new Purchase(2034, 350.00, "Supplies");
            Larry.ProcessRequest(p);

            p = new Purchase(2035, 32590.10, "Project X");
            Larry.ProcessRequest(p);

            p = new Purchase(2036, 122100.00, "Project Y");
            Larry.ProcessRequest(p);

            // Wait for user 
            Console.Read();
        }
    }

    // "Handler" 

    abstract class Approver
    {
        protected Approver successor;

        public void SetSuccessor(Approver successor)
        {
            this.successor = successor;
        }

        public abstract void ProcessRequest(Purchase purchase);
    }

    // "ConcreteHandler" 

    class Director : Approver
    {
        public override void ProcessRequest(Purchase purchase)
        {
            if (purchase.Amount < 10000.0)
            {
                Console.WriteLine("{0} approved request# {1}",
                  this.GetType().Name, purchase.Number);
            }
            else if (successor != null)
            {
                successor.ProcessRequest(purchase);
            }
        }
    }

    // "ConcreteHandler" 

    class VicePresident : Approver
    {
        public override void ProcessRequest(Purchase purchase)
        {
            if (purchase.Amount < 25000.0)
            {
                Console.WriteLine("{0} approved request# {1}",
                  this.GetType().Name, purchase.Number);
            }
            else if (successor != null)
            {
                successor.ProcessRequest(purchase);
            }
        }
    }

    // "ConcreteHandler" 

    class President : Approver
    {
        public override void ProcessRequest(Purchase purchase)
        {
            if (purchase.Amount < 100000.0)
            {
                Console.WriteLine("{0} approved request# {1}",
                  this.GetType().Name, purchase.Number);
            }
            else
            {
                Console.WriteLine(
                  "Request# {0} requires an executive meeting!",
                  purchase.Number);
            }
        }
    }

    // Request details 

    class Purchase
    {
        private int number;
        private double amount;
        private string purpose;

        // Constructor 
        public Purchase(int number, double amount, string purpose)
        {
            this.number = number;
            this.amount = amount;
            this.purpose = purpose;
        }

        // Properties 
        public double Amount
        {
            get { return amount; }
            set { amount = value; }
        }

        public string Purpose
        {
            get { return purpose; }
            set { purpose = value; }
        }

        public int Number
        {
            get { return number; }
            set { number = value; }
        }
    }
}