委托

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;

namespace MouseGame
{
    internal delegate void Feedback(int value);

    public sealed class Program
    {
        public static void Main()
        {

        }
        public static void StaticDelegateDemo()
        {
            Console.WriteLine("------------static delegate demo-------------");
            Counter(1, 3, null);
            Counter(1, 3, new Feedback(Program.FeedbackToConsole));
            Counter(1, 3, new Feedback(FeedbackToMsBox));
            Console.WriteLine();

        }
        //实例委托
        private static void InstanceDelegateDemo()
        {
            Console.WriteLine("------Instance Delegate Demo----------");
            Program p = new Program();
            Counter(1, 3,new Feedback(p.FeedbcakToFile));
            Console.WriteLine();
        }
        //链式委托1
        private static void ChainDelegateDemo1(Program p)
        {
            Console.WriteLine("--------Chain Delegate Demo 1----------");
            Feedback fb1 = new Feedback(FeedbackToConsole);
            Feedback fb2 = new Feedback(FeedbackToMsBox);
            Feedback fb3 = new Feedback(p.FeedbcakToFile);

            Feedback fbChain = null;
            fbChain = (Feedback)Delegate.Combine(fbChain, fb1);
            fbChain = (Feedback)Delegate.Combine(fbChain, fb2);
            fbChain = (Feedback)Delegate.Combine(fbChain, fb3);
            Counter(1, 3, fbChain);
            Console.WriteLine();

            fbChain = (Feedback)Delegate.Remove(fbChain, new Feedback(FeedbackToMsBox));
            Counter(1, 2, fbChain);
        }
        //链式委托2
        private static void ChainDelegateDemo2(Program p)
        {
            Console.WriteLine("--------Chain Delegate Demo 2 ------------");
            Feedback fb1 = new Feedback(FeedbackToConsole);
            Feedback fb2 = new Feedback(FeedbackToMsBox);
            Feedback fb3 = new Feedback(p.FeedbcakToFile);

            Feedback fbChain = null;
            fbChain += fb1;
            fbChain += fb2;
            fbChain += fb3;
            Counter(1, 2, fbChain);

            Console.WriteLine();
            fbChain -= new Feedback(FeedbackToMsBox);
            Counter(1, 2, fbChain);

        }

        private static void FeedbackToConsole(int value)
        {
            Console.WriteLine("Item=" + value);
        }
        private static void FeedbackToMsBox(int value)
        {
            System.Windows.Forms.MessageBox.Show("Item=" + value);
        }
        private void FeedbcakToFile(int value)
        {
            StreamWriter sw = new StreamWriter("status", true);
            sw.WriteLine("Ites="+value);
            sw.Close();
        }
        private static void Counter(int from, int to, Feedback fb)
        {
            for (int val = from; val <= to; val++)
            {
                if (fb != null)
                {
                    fb(val);
                }
            }
        }
    }

}