C#遍历访问Dictionary和HashTable

一般地Dictionary是按照元素的添加顺序输出的，这和HashTable不同。

Dictionary<int, string> dictionary = new Dictionary<int, string>();dictionary.Add(1, "xiaowang");dictionary.Add(21, "dsd");dictionary.Add(33, "dsfdfd");dictionary.Add(4, "liusang"); foreach (KeyValuePair<int, string> kvp in dictionary){    Console.WriteLine("key={0},value={1}", kvp.Key, kvp.Value);} foreach (int j in dictionary.Keys){    Console.WriteLine("key={0},value={1}", j, dictionary[j]);} Hashtable table = new Hashtable(); table.Add(1, "wang gang");table.Add(21, "xiao li");table.Add(33, "xiao fan");table.Add(4, "fff"); foreach (int i in table.Keys){    Console.WriteLine("key={0},value={1}", i, table[i]);} foreach (string str in table.Values){    Console.WriteLine("value={0}", str);} System.Collections.IDictionaryEnumerator d = table.GetEnumerator();while (d.MoveNext()){    System.Console.WriteLine("key={0},value={1}",d.Entry.Key,d.Entry.Value);} foreach (DictionaryEntry entry in table){    Console.WriteLine("key={0},value={1}", entry.Key, entry.Value);} Console.ReadLine();   输出结果： key=1,value=xiaowangkey=21,value=dsdkey=33,value=dsfdfdkey=4,value=liusangkey=1,value=xiaowangkey=21,value=dsdkey=33,value=dsfdfdkey=4,value=liusangkey=21,value=xiao likey=4,value=fffkey=1,value=wang gangkey=33,value=xiao fanvalue=xiao livalue=fffvalue=wang gangvalue=xiao fankey=21,value=xiao likey=4,value=fffkey=1,value=wang gangkey=33,value=xiao fankey=21,value=xiao likey=4,value=fffkey=1,value=wang gangkey=33,value=xiao fan

Dictionary 通过索引指定下标访问指定键和值 || Dictionary_Value重新赋值

Dictionary <int ,int > data = new Dictionary <int ,int >(); data.Add(1,100); data.Add(2,100); data.Add(3,200); data.Add(4,100);    data.Keys.ElementAt(0);    data.Values.ElementAt(0);

 

c# Dictionary 通过索引指定下标访问指定键和值

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=============  dictionary的遍历及赋值问题 ====Dictionary_Value重新赋值===========

Dictionary<int, string> datatable = new Dictionary<int, string>();datatable.Add(1, "hello 1");datatable.Add(2, "hello 2");int[] keys = datatable.Keys.ToArray();for (int i = 0; i < keys.Length; i++){    if (datatable[keys[i]] == "hello 2")    {        datatable[keys[i]] = "hello";                     <<<<赋值方法为    }}

Dictionary  终极用法

 

using System;   using System.Collections.Generic;     class DictionaryDemo   {       static void Main(string[] args)       {           DictionaryDemo001();           Console.ReadLine();             DictionaryDemo002();           Console.ReadLine();             DictionaryDemo003();           Console.ReadLine();       }         /// <summary>       /// 一般用法       /// </summary>       static void DictionaryDemo001()       {           Dictionary<int, string> dict = new Dictionary<int, string>();           dict.Add(1, "111");           dict.Add(2, "222");             //判断是否存在相应的key并显示           if (dict.ContainsKey(2))           {               Console.WriteLine(dict[2]);           }             //遍历Keys           foreach (var item in dict.Keys)           {               Console.WriteLine("Key:{0}", item);           }             //遍历Values           foreach (var item in dict.Values)           {               Console.WriteLine("value:{0}", item);           }             //遍历整个字典           foreach (var item in dict)           {               Console.WriteLine("key:{0} value:{1}", item.Key, item.Value);           }       }         /// <summary>       /// 参数为其它类型       /// </summary>       static void DictionaryDemo002()       {           Dictionary<string, string[]> dict = new Dictionary<string, string[]>();           dict.Add("1", "1,11,111".Split(','));           dict.Add("2", "2,22,222".Split(','));           Console.WriteLine(dict["2"][2]);       }         /// <summary>       /// 调用自定义类       /// </summary>       static void DictionaryDemo003()       {           Dictionary<int, yongfa365> dict = new Dictionary<int, yongfa365>();           for (int i = 0; i < 10; i++)           {               yongfa365 y = new yongfa365();               y.UserCode = i;               y.UserName = "com " + i.ToString();               dict.Add(i, y);           }           foreach (var item in dict)           {               Console.WriteLine("{0} One:{1} UserName:{2}", item.Key, item.Value.UserCode, item.Value.UserName);           }       }   }     class yongfa365   {       public int UserCode { get; set; }       public string UserName { get; set; }     }   

本文转自网络，为两篇文章的合并：

http://hi.baidu.com/zkbob22/blog/item/d5aadfd26f96b7133bf3cf4d.html

 

http://www.cnblogs.com/blsong/archive/2010/08/18/1802382.html