C# dictionary

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Demo1
{
    class Program
    {
        static void Main(string[] args)
        {
            //创建泛型哈希表,Key类型为int,Value类型为string
            Dictionary<int, string> myDictionary = new Dictionary<int, string>();
            //1.添加元素
            myDictionary.Add(1, "a");
            myDictionary.Add(2, "b");
            myDictionary.Add(3, "c");
            //2.删除元素
            myDictionary.Remove(3);
            //3.假如不存在元素则添加元素
            if (!myDictionary.ContainsKey(4))
            {
                myDictionary.Add(4, "d");
            }
            //4.显示容量和元素个数
            Console.WriteLine("元素个数:{0}",myDictionary.Count);
            //5.通过key查找元素
            if (myDictionary.ContainsKey(1))
            {
                Console.WriteLine("key:{0},value:{1}","1", myDictionary[1]);
                Console.WriteLine(myDictionary[1]);            
            }
            //6.通过KeyValuePair遍历元素
            foreach (KeyValuePair<int,string>kvp in myDictionary)
            {
                Console.WriteLine("key={0},value={1}", kvp.Key, kvp.Value);

            }
            //7.得到哈希表键的集合
            Dictionary<int, string>.KeyCollection keyCol = myDictionary.Keys;
                //遍历键的集合
                foreach (int n in keyCol)
                {
                    Console.WriteLine("key={0}", n);                
                }
            //8.得到哈希表值的集合
            Dictionary<int, string>.ValueCollection valCol = myDictionary.Values;
                //遍历值的集合
                foreach( string s in valCol)
                {
                Console.WriteLine("value:{0}",s);
                }
            //9.使用TryGetValue方法获取指定键对应的值
            string slove = string.Empty;
            if (myDictionary.TryGetValue(5, out slove))
            {
                Console.WriteLine("查找结果:{0}", slove);
            }
            else
            {
                Console.WriteLine("查找失败");
            }
            //10.清空哈希表
            //myDictionary.Clear();
            Console.ReadKey();
        }
    }
}
转载:https://www.cnblogs.com/unity3ds/p/11168635.html
posted @ 2020-04-14 21:26  .net&new  阅读(657)  评论(0编辑  收藏  举报