head first 设计模式学习随笔(10)----组合模式

所谓组合模式----允许将对象组合形成树形结构来表现“整体/部分”层次结构。组合能让客户以一致的方式处理个别对象以及对象集合

个人认为Xml数据的格式就很类似于组合模式，而XmlNode类适合于组合模式的描述，以下我将以长江源头描述起，来说明组合模式

 

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();
 }
 }