摘要：using System;using System.Collections.Generic;using System.Linq;using System.Text;namespace Dictionary键值对 { class Program { &n
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Dictionary键值对
{ class Program
{ static void Main(string[] args)
{
DicSample1();
DicSample2();
DicSample3();
DicSample4();
Console.Read();
} //1、用法1： 常规用
// 增加键值对之前需要判断是否存在该键，如果已经存在该键而且不判断，将抛出异常。所以这样每次都要进行判断，很麻烦，在备注里使用了一个扩展方法
public static void DicSample1()
{
Dictionary<String, String> pList = new Dictionary<String, String>(); try
{ if (pList.ContainsKey("Item1") == false)
{
pList.Add("Item1", "ZheJiang");
} if (pList.ContainsKey("Item2") == false)
{
pList.Add("Item2", "ShangHai");
} else
{
pList["Item2"] = "ShangHai";
} if (pList.ContainsKey("Item3") == false)
{
pList.Add("Item3", "BeiJiang");
}
} catch (System.Exception e)
{
Console.WriteLine("Error: {0}", e.Message);
} //判断是否存在相应的key并显示
if (pList.ContainsKey("Item1"))
{
Console.WriteLine("Output: " + pList["Item1"]);
} //遍历Key
foreach (var key in pList.Keys)
{
Console.WriteLine("Output Key: {0}", key);
} //遍历Value
foreach (String value in pList.Values)
{
Console.WriteLine("Output Value: {0}", value);
} //遍历Key和Value
foreach (var dic in pList)
{
Console.WriteLine("Output Key : {0}, Value : {1} ", dic.Key, dic.Value);
}
} //2、用法2：Dictionary的Value为一个数组
/// <summary>
/// Dictionary的Value为一个数组
/// </summary>
public static void DicSample2()
{
Dictionary<String, String[]> dic = new Dictionary<String, String[]>(); String[] ZheJiang = { "Huzhou", "HangZhou", "TaiZhou" }; String[] ShangHai = { "Budong", "Buxi" };
dic.Add("ZJ", ZheJiang);
dic.Add("SH", ShangHai);
Console.WriteLine("Output :" + dic["ZJ"][0]);
} //3、用法3： Dictionary的Value为一个类
//Dictionary的Value为一个类
public static void DicSample3()
{
Dictionary<String, Student> stuList = new Dictionary<String, Student>();
Student stu = null; for (int i = 0; i < 3; i++)
{
stu = new Student();
stu.Name = i.ToString();
stu.Name = "StuName" + i.ToString();
stuList.Add(i.ToString(), stu);
}
foreach (var student in stuList)
{
Console.WriteLine("Output : Key {0}, Num : {1}, Name {2}", student.Key, student.Value.Name, student.Value.Name);
}
}
//4 备注：Dictionary的扩展方法使用
/// <summary>
/// Dictionary的扩展方法使用
/// </summary>
public static void DicSample4()
{ //1)普通调用
Dictionary<int, String> dict = new Dictionary<int, String>();
DictionaryExtensionMethodClass.TryAdd(dict, 1, "ZhangSan");
DictionaryExtensionMethodClass.TryAdd(dict, 2, "WangWu");
DictionaryExtensionMethodClass.AddOrPeplace(dict, 3, "WangWu");
DictionaryExtensionMethodClass.AddOrPeplace(dict, 3, "ZhangWu");
DictionaryExtensionMethodClass.TryAdd(dict, 2, "LiSi"); //2)TryAdd 和 AddOrReplace 这两个方法具有较强自我描述能力，用起来很省心，而且也简单：
dict.AddOrPeplace(20, "Orange");
dict.TryAdd(21, "Banana");
dict.TryAdd(22, "apple"); //3)像Linq或jQuery一样连起来写
dict.TryAdd(10, "Bob")
.TryAdd(11, "Tom")
.AddOrPeplace(12, "Jom"); //4) 获取值
String F = "Ba";
dict.TryGetValue(31, out F);
Console.WriteLine("F : {0}", F);
foreach (var dic in dict)
{
Console.WriteLine("Output : Key : {0}, Value : {1}", dic.Key, dic.Value);
} //5)下面是使用GetValue获取值
var v1 = dict.GetValue(111, null); var v2 = dict.GetValue(10, "abc"); //6)批量添加
var dict1 = new Dictionary<int, int>();
dict1.AddOrPeplace(3, 3);
dict1.AddOrPeplace(5, 5); var dict2 = new Dictionary<int, int>();
dict2.AddOrPeplace(1, 1);
dict2.AddOrPeplace(4, 4);
dict2.AddRange(dict1, false);
}
} //Student类：
public class Student
{ public String Num { get; set; } public String Name { get; set; }
} //扩展方法所在的类
public static class DictionaryExtensionMethodClass
{ /// <summary>
/// 尝试将键和值添加到字典中：如果不存在，才添加；存在，不添加也不抛导常
/// </summary>
public static Dictionary<TKey, TValue> TryAdd<TKey, TValue>(this Dictionary<TKey, TValue> dict, TKey key, TValue value)
{ if (dict.ContainsKey(key) == false)
dict.Add(key, value); return dict;
} /// <summary>
/// 将键和值添加或替换到字典中：如果不存在，则添加；存在，则替换
/// </summary>
public static Dictionary<TKey, TValue> AddOrPeplace<TKey, TValue>(this Dictionary<TKey, TValue> dict, TKey key, TValue value)
{
dict[key] = value; return dict;
} /// <summary>
/// 获取与指定的键相关联的值，如果没有则返回输入的默认值
/// </summary>
public static TValue GetValue<TKey, TValue>(this Dictionary<TKey, TValue> dict, TKey key, TValue defaultValue)
{ return dict.ContainsKey(key) ? dict[key] : defaultValue;
} /// <summary>
/// 向字典中批量添加键值对
/// </summary>
/// <param name="replaceExisted">如果已存在，是否替换</param>
public static Dictionary<TKey, TValue> AddRange<TKey, TValue>(this Dictionary<TKey, TValue> dict, IEnumerable<KeyValuePair<TKey, TValue>> values, bool replaceExisted)
{
foreach (var item in values)
{ if (dict.ContainsKey(item.Key) == false || replaceExisted)
dict[item.Key] = item.Value;
} return dict;
}
}
}
