C#实现自定义Dictionary类实例

class MyDictioinary<TKey, TValue>{ LinkedList<KeyValuePair<TKey, TValue>> llDictionary  = new LinkedList<KeyValuePair<TKey, TValue>>(); /// <summary> /// 索引器，输入TKey可以找到对应的TValue /// </summary> /// <param name="tk">键值</param> /// <returns></returns> public TValue this[TKey tk] {  get  {   foreach(KeyValuePair<TKey, TValue> kvp in llDictionary)   {    if (tk.Equals(kvp.Key))    {     return kvp.Value;    }   }   return default(TValue);  } } /// <summary> /// 添加一组数据 /// </summary> /// <param name="tk"></param> /// <param name="tv"></param> public void Add(TKey tk, TValue tv) {  foreach (KeyValuePair<TKey, TValue> kvp in llDictionary)  {   if (tk.Equals(kvp.Key))   {    throw new Exception("新增失败：主键已经存在");   }  }  llDictionary.AddLast(new KeyValuePair<TKey, TValue>(tk, tv)); } /// <summary> /// 删除一组数据 /// </summary> /// <param name="tk"></param> public void Delete(TKey tk) {  foreach (KeyValuePair<TKey, TValue> kvp in llDictionary)  {   if (tk.Equals(kvp.Key))   {    llDictionary.Remove(kvp);    return;   }   }  throw new Exception("删除失败：不存在这个主键"); } /// <summary> /// 修改一组数据 /// </summary> /// <param name="tk"></param> /// <param name="tv"></param> public void Modify(TKey tk, TValue tv) {  LinkedListNode<KeyValuePair<TKey, TValue>> lln = llDictionary.First;  while (lln != null )  {   if (tk.Equals(lln.Value.Key))   {    llDictionary.AddBefore(lln, new KeyValuePair<TKey, TValue>(tk, tv));    llDictionary.Remove(lln);    return;   }   lln = lln.Next;  }  throw new Exception("修改失败：不存在这个主键"); } /// <summary> /// 打印整个Dictionary内的全部数据 /// </summary> public void PrintData() {  Console.WriteLine("==================");  Console.WriteLine("输出数据");  Console.WriteLine("==================");  foreach (KeyValuePair<TKey, TValue> kvp in llDictionary)  {   Console.WriteLine(kvp.Key.ToString() + "/t:" + kvp.Value.ToString());  }  Console.WriteLine(string.Format("共计输出 {0} 项", llDictionary.Count));  Console.WriteLine(DateTime.Now.ToLongTimeString());  Console.WriteLine("=================="); } /// <summary> /// 决定按什么顺序打印Dictionary内的数据 /// </summary> public enum PrintType {  Normal = 0, //不排序  Ascend = 1, //升序排列  Descend = 2 //降序佩列 }; /// <summary> /// 返回List类型的数据 /// </summary> /// <param name="printType">List内数据的排序情况</param> /// <returns></returns> public List<KeyValuePair<TKey, TValue>> ToList(PrintType printType = PrintType.Normal) {  switch (printType)  {   case PrintType.Normal:    {     return llDictionary.ToList();    }   case PrintType.Ascend:    {     if (llDictionary.Count == 0) return null;     LinkedList<KeyValuePair<TKey, TValue>> newll =       new LinkedList<KeyValuePair<TKey, TValue>>();     try     {      LinkedListNode<KeyValuePair<TKey, TValue>> lln = llDictionary.First;      while (lln != null)      {       LinkedListNode<KeyValuePair<TKey, TValue>> lln2 = newll.First;       while (lln2 != null)       {        //Key是字符串的情况        if (llDictionary.First.Value.Key.GetType() ==          "string".GetType())        {         if (string.Compare(lln2.Value.Key.ToString(),          lln.Value.Key.ToString()) > 0)         {          newll.AddBefore(lln2, new LinkedListNode           <KeyValuePair<TKey, TValue>>(lln.Value));          break;         }        }        else //Key可以被转化为浮点数的情况        {         if (double.Parse(lln2.Value.Key.ToString()) >          double.Parse(lln.Value.Key.ToString()))         {          newll.AddBefore(lln2, new LinkedListNode           <KeyValuePair<TKey, TValue>>(lln.Value));          break;         }        }        lln2 = lln2.Next;       }       if (lln2 == null)       {        newll.AddLast(new LinkedListNode         <KeyValuePair<TKey, TValue>>(lln.Value));       }       lln = lln.Next;      }     }     catch (Exception ex)     {      Console.WriteLine(ex.Message);     }     return newll.ToList();    }   case PrintType.Descend:    {     if (llDictionary.Count == 0) return null;     LinkedList<KeyValuePair<TKey, TValue>> newll =      new LinkedList<KeyValuePair<TKey, TValue>>();     try     {      LinkedListNode<KeyValuePair<TKey, TValue>> lln = llDictionary.First;      while (lln != null)      {       LinkedListNode<KeyValuePair<TKey, TValue>> lln2 = newll.First;       while (lln2 != null)       {        //Key是字符串的情况        if (llDictionary.First.Value.Key.GetType() ==          "string".GetType())        {         if (string.Compare(lln2.Value.Key.ToString(),          lln.Value.Key.ToString()) < 0)         {          newll.AddBefore(lln2, new LinkedListNode           <KeyValuePair<TKey, TValue>>(lln.Value));          break;         }        }        else //Key可以被转化为浮点数的情况        {         if (double.Parse(lln2.Value.Key.ToString()) <          double.Parse(lln.Value.Key.ToString()))         {          newll.AddBefore(lln2, new LinkedListNode           <KeyValuePair<TKey, TValue>>(lln.Value));          break;         }        }        lln2 = lln2.Next;       }       if (lln2 == null)       {        newll.AddLast(new LinkedListNode         <KeyValuePair<TKey, TValue>>(lln.Value));       }       lln = lln.Next;      }     }     catch (Exception ex)     {      Console.WriteLine(ex.Message);     }     return newll.ToList();    }   default: return null;  } }}

static void Main(string[] args){ MyDictioinary<string, string> dic = new MyDictioinary<string, string>(); //插入两组数据 dic.Add("1", "MERCURY"); dic.Add("2", "VENUS"); //尝试插入重复主键的数据 报警：主键不存在 try {  dic.Add("1", "EARTH"); } catch (Exception ex) {  Console.WriteLine(ex.Message); } //删除一组数据 dic.Delete("1"); //添加一组数据 dic.Add("1", "MARS"); //修改两组数据 dic.Modify("1", "JUPITER"); dic.Modify("2", "SATURN"); //添加两组数据 dic.Add("6", "SUN"); dic.Add("5", "MOON"); dic.Add("8", "URANUS"); dic.Add("9", "NEPTUNE"); dic.PrintData(); //通过索引找到对应值 Console.WriteLine("key为6的元素value为：" + dic["6"]); Console.WriteLine("key为3的元素value为：" + dic["3"]); List<KeyValuePair<string, string>> l; //输出升序排列好的List l = dic.ToList(MyDictioinary<string, string>.PrintType.Ascend); Console.WriteLine("升序排列后的List："); for (int i = 0; i < l.Count; i++) {  Console.WriteLine(l[i].Key.ToString() + "/t:" + l[i].Value.ToString()); } //输出降序排列好的List l = dic.ToList(MyDictioinary<string, string>.PrintType.Descend); Console.WriteLine("降排列后的List："); for (int i = 0; i < l.Count; i++) {  Console.WriteLine(l[i].Key.ToString() + "/t:" + l[i].Value.ToString()); } Console.ReadLine();}