Code
    /// <summary>
    /// 组合模式 抽象类
    /// </summary>
    public abstract class Component
    {
        public abstract string GetInfo();
        public abstract List<Component> GetChilds();
        public abstract void AddChild(Component com);
        public abstract void RemoveChild(Component com);

        /// <summary>
        /// 打印全部信息
        /// </summary>
        public void PrintAll()
        {
            Print(this,0);
        }

        /// <summary>
        /// 递归方法遍历所有
        /// </summary>
        /// <param name="com"></param>
        /// <param name="i"></param>
        private void Print(Component com,int i) 
        {
            Console.WriteLine(GetTab(i) + com.GetInfo());
            List<Component> childs =com.GetChilds();
            if (childs != null)
            {
                foreach (Component list in childs)
                    Print(list, ++i);
            }
        }

        /// <summary>
        /// 这里是tab 为了使得层次更加清晰
        /// </summary>
        /// <param name="i"></param>
        /// <returns></returns>
        private string GetTab(int i)
        {
            string tab="";
            for (int j = 0; j < i; j++)
                tab += "\t";
            return tab;
        }
    }

    /// <summary>
    /// 河 可以有分支溪流组成
    /// </summary>
    public class River : Component
    {
        List<Component> Rivers;
        string info;

        public River(string info)
        {
            Rivers = new List<Component>();
            this.info = info;
        }

        public override string GetInfo()
        {
            return info;
        }

        public override List<Component> GetChilds()
        {
            return this.Rivers;
        }

        public override void AddChild(Component com)
        {
            Rivers.Add(com);
        }

        public override void RemoveChild(Component com)
        {
            Rivers.Remove(com);
        }
    }

    /// <summary>
    /// 溪流 没有分支啦
    /// </summary>
    public class Rivulet : Component
    {
        string info;

        public Rivulet(string info)
        {
            this.info = info;
        }

        public override string GetInfo()
        {
            return info;
        }

        public override List<Component> GetChilds()
        {
            return null;
        }

        #region 以下2个方法不实现

            public override void AddChild(Component com)
            {
                throw new NotImplementedException();
            }

            public override void RemoveChild(Component com)
            {
                throw new NotImplementedException();
            }

        #endregion

    }


    class Program
    {
        static void Main(string[] args)
        {
            River changjiang = new River("长江");
            River yalongjiang = new River("雅砻江");
            River minjiang = new River("岷江");

            Rivulet tuotuohe = new Rivulet("沱沱河");
            Rivulet tongtianhe = new Rivulet("通天河");
            Rivulet daduhe = new Rivulet("大渡河");
            Rivulet jialingjiang = new Rivulet("嘉陵江");
            Rivulet wujiang = new Rivulet("乌江");
            Rivulet yuanjiang = new Rivulet("沅江");
            Rivulet xiangjiang = new Rivulet("湘江");
            Rivulet hanjiang = new Rivulet("汉江");
            Rivulet ganjiang = new Rivulet("赣江");
            Rivulet huangpujiang = new Rivulet("黄浦江");

            yalongjiang.AddChild(daduhe);
            yalongjiang.AddChild(jialingjiang);
            yalongjiang.AddChild(wujiang);

            minjiang.AddChild(yuanjiang);
            minjiang.AddChild(xiangjiang);
            minjiang.AddChild(hanjiang);
            minjiang.AddChild(ganjiang);

            changjiang.AddChild(tuotuohe);
            changjiang.AddChild(tongtianhe);
            changjiang.AddChild(yalongjiang);
            changjiang.AddChild(minjiang);
            changjiang.AddChild(huangpujiang);

            changjiang.PrintAll();

            Console.Read();
        }
    }

Code
    /// <summary>
    /// 迭代器模式接口
    /// </summary>
    public interface Iterator 
    {
        bool HasNext();
        object Next();
    }

    /// <summary>
    /// 一种带数组成员类
    /// </summary>
    public class Worms : Iterator 
    {
        string[] worms;
        int nums = -1;

        public Worms(string[] worms) 
        {
            this.worms = worms;
        }

        #region Iterator Members

        public bool HasNext()
        {
            if (worms.Length > nums + 1)
            {
                nums += 1;
                return true;
            }
            else
                return false;
        }

        public object Next()
        {
            return worms[nums];
        }

        #endregion
    }


    /// <summary>
    /// 一种带泛型成员类
    /// </summary>
    public class Duck : Iterator
    {
        List<string> ducks;
        int nums = -1;

        public Duck(List<string> ducks) 
        {
            this.ducks = ducks;
        }
        #region Iterator Members

        public bool HasNext()
        {
            if (ducks.Count > nums+1)
            {
                nums += 1;
                return true;
            }
            else
                return false;
        }

        public object Next()
        {
            return ducks[nums];
        }

        #endregion
    }


    public class Info
    {
        Worms worms;
        Duck ducks;

        public Info(Worms worms,Duck ducks)
        {
            this.worms = worms;
            this.ducks = ducks;
        }

        public void ReadIterator(string type)
        {
            if (type == "ducks")
                Read(ducks);
            if (type == "worms")
                Read(worms);
        }

        //统一遍历接口
        private void Read(Iterator i)
        {
            while(i.HasNext())
                Console.WriteLine(i.Next().ToString());
        }
    }


    class Program
    {
        static void Main(string[] args)
        {
            Worms worms = new Worms(new string[] { "毛毛虫", "鼻涕虫", "蚂蚁", "苍蝇", "蚊子", "瓢虫", "蟋蟀", "蜈蚣" });
            Duck ducks = new Duck(new List<string> { "鸳鸯", "鹅", "黄头鸭", "北京填鸭", "绿头鸭", "白头鸭", "黑鸭鸭", "白鸭鸭", "长嘴鸭", "无毛鸭" });

            Info info = new Info(worms, ducks);

            info.ReadIterator("ducks");
            Console.WriteLine("-------------华丽的分割线----------------");
            info.ReadIterator("worms");

            Console.Read();
        }
    }