dictionaryc#stringtableclasssystem
一般地Dictionary是按照元素的添加顺序输出的，这和HashTable不同。
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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=xiaowang
key=21,value=dsd
key=33,value=dsfdfd
key=4,value=liusang
key=1,value=xiaowang
key=21,value=dsd
key=33,value=dsfdfd
key=4,value=liusang
key=21,value=xiao li
key=4,value=fff
key=1,value=wang gang
key=33,value=xiao fan
value=xiao li
value=fff
value=wang gang
value=xiao fan
key=21,value=xiao li
key=4,value=fff
key=1,value=wang gang
key=33,value=xiao fan
key=21,value=xiao li
key=4,value=fff
key=1,value=wang gang
key=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
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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===========
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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[csharp] view plaincopy
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; }     }