委托的实例：

class Program
    {
        static void Main(string[] args)
        {
            Teacher Tc = new Teacher("赵老师");    //实例化老师和学生
            Student St1 = new Student("张三");
            Student St2 = new Student("李四");

            //把学生的行为交给 委托
            Tc.TeacherCome += new Teacher.EventHandler(St1.StopCopyWork);   
            Tc.TeacherCome += new Teacher.EventHandler(St2.StopWhisper);    

            Tc.Come();

        }
    }

    class Teacher
    {
        private string name;
        public Teacher(string name)
        {
            this.name = name;
        }
        public delegate void EventHandler();        //声明一个委托EventHandler
        public event EventHandler TeacherCome;      //声明事件名称，事件类型为EventHandler
        public void Come()                          //老师的行为
        {
            Console.WriteLine("{0}来了", name);       
            if (TeacherCome != null)            //如果需要委托，则执行下面程序
            {
                TeacherCome();                  
            }
        }
    }
    class Student
    {
        private string name;
        public Student(string name)
        {
            this.name = name;
        }
        public void StopWhisper()
        {
            Console.WriteLine("老师来了，{0}停止说话",name);
        }
        public void StopCopyWork()
        {
            Console.WriteLine("老师来了，{0}停止抄作业",name);
        }
    }

运行结果：

代理模式：

      为其他对象提供一种代理，来帮助达到目的。

代理模式实例：

class Program
    {
        static void Main(string[] args)
        {
            SchoolGirl mm = new SchoolGirl();
            mm.Name = "jiaojiao";

            Proxy daili = new Proxy(mm);

            daili.GiveDolls();
            daili.GiveFlowers();
            daili.GiveChocolate();
        }
    }

    class SchoolGirl            //定义 女孩类
    {
        private string name;
        public string Name
        {
            get { return name; }
            set { name = value; }
        }
    }

    interface IGiveGift        //创建一个送礼物的接口
    {
        void GiveDolls();
        void GiveFlowers();
        void GiveChocolate();
    }
    class Pursuit:IGiveGift     //追求者类，使用送礼物的接口
    {
        SchoolGirl mm;          //要追求女孩的名字
        public Pursuit(SchoolGirl mm)
        {
            this.mm = mm;
        }
        public void GiveDolls()
        {
            Console.WriteLine(mm.Name+"送你洋娃娃"