在日常開發中，經常遇到對樹的操作，我們可以利用泛型和委托對這些樹進行操作，這樣就不需要每有一個樹就要實現相應的功能了。

源碼在http://files.cnblogs.com/haiconc/LangTest.zip

首先，使用類泛型聲明：

?public class TreeOperator<T,K>

在類內聲明三個委托

??????? public delegate K GetTreeKey(T tree);//取得樹的Key
??????? GetTreeKey GTK;

??????? public delegate K GetParentKey(T tree);//取得樹的父節點
??????? GetParentKey GPK;

??????? public delegate bool IsKeyEqual(K keyA, K keyB);//比較Key是否相等
??????? IsKeyEqual IKE;

數據源：

?????? List<T> source;

構造函數：

?public int MaxDeep = 100;//防止在遞歸過程中進入無限死循環

?public TreeOperator(GetTreeKey gti, GetParentKey gtp, IsKeyEqual ike , List<T> source, int deep)
??????? {
??????????? this.GTK = gti;
??????????? this.GPK = gtp;
??????????? this.IKE = ike;
??????????? this.source = source;
??????????? this.MaxDeep = deep;
??????? }

實現第一個功能

??????? /// <summary>
??????? /// 取得從根樹到某個樹的路徑
??????? /// </summary>
??????? /// <param name="tree">某個樹</param>
??????? /// <param name="RootTree">根樹</param>
??????? /// <returns></returns>
??????? public List<T> GetTreePath(T tree, T RootTree)
??????? {
??????????? List<T> list = new List<T>();
??????????? T temp = tree;

??????????? int i = 0;
??????????? while (!IKE(GTK(temp), GTK(RootTree)))
??????????? {
??????????????? list.Add(temp);
??????????????? temp = GetParentTreeByTree(temp);
??????????????? /* 防止進入死循環 */
??????????????? i++;
??????????????? while (i > MaxDeep)
??????????????? {
??????????????????? break;
??????????????? }
??????????? }
??????????? list.Add(RootTree);
??????????? list.Reverse();

??????????? return list;
??????? }

??????? private T GetTreeByKey(K key)
??????? {
??????????? foreach (T tee in source)
??????????? {
??????????????? if(IKE(GTK(tee),key))
??????????????????? return tee;
??????????? }
??????????? return default(T);
??????? }


??????? private T GetParentTreeByTree(T tree)
??????? {
??????????? K key = GPK(tree);

??????????? return GetTreeByKey(key);
??????? }
第二個功能實現：

?? /// <summary>
??????? /// 取得某個樹的所有子孫樹
??????? /// </summary>
??????? /// <param name="tree"></param>
??????? /// <param name="source"></param>
??????? /// <returns></returns>
??????? public List<T> GetAllSubTree(T tree)
??????? {
??????????? List<T> list = new List<T>();

??????????? int deep = 0;
??????????? foreach (T tee in source)
??????????? {
??????????????? if(IKE(GPK(tee),GTK(tree)))
??????????????? {
??????????????????? list.Add(tee);
??????????????????? AddSub(tee, source, list, deep + 1);
??????????????? }
??????????? }

??????????? return list;
??????? }

??????? private void AddSub(T tree, List<T> source,List<T> list ,int deep )
??????? {
??????????? if (deep > MaxDeep) return;
??????????? foreach (T tee in source)
??????????? {
??????????????? if (IKE(GPK(tee), GTK(tree)))
??????????????? {
??????????????????? list.Add(tee);
??????????????????? AddSub(tee, source, list, deep + 1);
??????????????? }
??????????? }
??????? }
程序匆忙寫成，有待改進。

源碼在http://files.cnblogs.com/haiconc/LangTest.zip

轉載于:https://www.cnblogs.com/haiconc/archive/2012/02/12/2347769.html

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