51. C# -- Directonary字典

[b]C# Dictionary 字典[/b]

说明
必须包含名空间System.Collection.Generic
Dictionary里面的每一个元素都是一个键值对(由二个元素组成：键和值)
键必须是唯一的,而值不需要唯一的
键和值都可以是任何类型(比如：string, int, 自定义类型，等等)
通过一个键读取一个值的时间是接近O(1)
键值对之间的偏序可以不定义
使用方法，代码：

using System;
using System.Collections.Generic;
namespace LambdaDemo
{
class Program
{
static void Main(string[] args)
{
//定义
Dictionary<string, string> openWith = new Dictionary<string, string>();
//添加元素
openWith.Add("txt","notepad.exe");
openWith.Add("bmp", "otepad.exe");
openWith.Add("dib", "paint.exe");
openWith.Add("rtf", "wordpad.exe");
//取值
Console.WriteLine("For key = \"rtf\", value = {0}.", openWith["rtf"]);
//更改值
openWith["rtf"] = "winword.exe";
Console.WriteLine("For key = \"rtf\", value = {0}.", openWith["rtf"]);
//遍历key
foreach (string key in openWith.Keys)
{
Console.WriteLine("Key = {0}", key);
}
//遍历value
foreach (string value in openWith.Values)
{
Console.WriteLine("value = {0}", value);
}
//遍历value, Second Method
Dictionary<string, string>.ValueCollection valueColl = openWith.Values;
foreach (string s in valueColl)
{
Console.WriteLine("Second Method, Value = {0}", s);
}
//遍历字典
foreach (KeyValuePair<string, string> kvp in openWith)
{
Console.WriteLine("Key = {0}, Value = {1}", kvp.Key, kvp.Value);
}
//添加存在的元素
try
{
openWith.Add("txt", "winword.exe");
}
catch (ArgumentException)
{
Console.WriteLine("An element with Key = \"txt\" already exists.");
}
//删除元素
openWith.Remove("doc");
if (!openWith.ContainsKey("doc"))
{
Console.WriteLine("Key \"doc\" is not found.");
}
Console.ReadLine();
　
//参数为其它类型
Dictionary<int, string[]> OtherType = new Dictionary<int, string[]>();
OtherType.Add(1, "1,11,111".Split(','));
OtherType.Add(2, "2,22,222".Split(','));
Console.WriteLine(OtherType[1][2]);

//声明并添加元素
Dictionary<int, DouCube> MyType = new Dictionary<int, DouCube>();
for(int i = 1; i <= 9; i++)
{
DouCube element = new DouCube();
element.Code = i * 100;
element.Page = "http://www.doucube.com/" + i.ToString() + ".html";
MyType.Add(i, element);
}
//遍历元素
foreach (KeyValuePair<int, DouCube> kvp in MyType)
{
Console.WriteLine("Index {0} Code:{1} Page:{2}", kvp.Key, kvp.Value.Code, kvp.Value.Page);
}
Console.ReadLine();
}
//参数为自定义类型,自定义类
class DouCube
{
public int Code { get { return _Code; } set { _Code = value; } } private int _Code;
public string Page { get { return _Page; } set { _Page = value; } } private string _Page;
}

}
}

结果：




参考：
http://www.cnblogs.com/txw1958/archive/2012/11/07/csharp-dictionary.html