C#中Dictionary的介绍

青旅半醒 2021-09-17 12:26 504阅读 0赞

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：" + 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key的集合
                Dictionary<int, string>.KeyCollection keyCol = myDictionary.Keys;
                foreach (int n in keyCol)
                {
                    Console.WriteLine("key={0}", n);
                }
    
                //8.得到哈希表value的集合
                Dictionary<int, string>.ValueCollection valueCol = myDictionary.Values;
                foreach (string s in valueCol)
                {
                    Console.WriteLine("value={0}", s);
                }
    
                //10.清空哈希表
                myDictionary.Clear();
    
                Console.ReadKey();
            }
          
        }

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[20190105145745584.png]: /images/20210725/c62fab682d3341d8ab86fe4f646b5dea.png