C#-字典(Dictionary)用法

2026-04-22 约 547 字预计阅读 2 分钟

字典(Dictionary)是一种非常有用的数据结构，它存储键值对(key-value pairs)。字典中的每个键都是唯一的，并且每个键都是唯一的，并且每个键映射到一个值。字典提供了快速的查找、添加和删除键值对的能力。

        
        
        
    
namespace demo
{
    internal class Program
    {
        static void Main(string[] args)
        {
            // 1.字典初始化
            Dictionary<int, string> dict = new Dictionary<int, string>();

            dict = new Dictionary<int, string>()
            {
                {1, "Value1"},
                {2, "Value2"},
                {3, "Value3"},
                {4, "Value4"},
                {5, "Value5"}
            };

            // 添加元素
            dict.Add(6, "Value6");
            dict.Add(7, "Value7");
            dict.Add(8, "Value8");
            dict.Add(9, "Value9");

            // 2.列表与字典转换
            List<string> DataListA = new List<string> { "A", "B", "C", "D", "E", "F" };
            List<int> DataListB = new List<int> { 100, 200, 300, 400, 500, 600 };

            // 列表转换为字典
            dict = ListToDictionary(DataListA);
            dict = ListToDictionary(DataListB);

            // 将字典转换为列表
            DataListA = DictionaryToList(dict);


            // 3.字典遍历、查找、删除

            // 通过KeyValuePair遍历字典
            foreach (KeyValuePair<int, string> keyValuePair in dict)
            {
                Console.WriteLine($"Key: {keyValuePair.Key}, Value: {keyValuePair.Value}");
            }

            // 通过Key查找元素
            if (dict.ContainsKey(3))
            {
                string v1 = dict[3];
                Console.WriteLine("Key:{0}, Value:{1}", "3", dict[3]);
            }

            // 通过Remove 方法移除指定的键值
            if (dict.ContainsKey(1))
            {
                Console.WriteLine("Key:{0},Value:{1}", "1", dict[1]);
                dict.Remove(1);
            }
            else
            {
                Console.WriteLine("不存在 Key : 1");
            }
        }

        /// <summary>
        /// 将字典转换为列表
        /// </summary>
        public static List<string> DictionaryToList(Dictionary<int, string> dict)
        {
            List<string> RetList = new List<string>();

            // 通过KeyValuePair遍历字典
            foreach (KeyValuePair<int, string> keyValuePair in dict)
            {
                RetList.Add(keyValuePair.Value);
            }

            return RetList;
        }

        /// <summary>
        /// 将列表转换为字典
        /// </summary>
        /// <param name="DataList">字符串列表</param>
        public static Dictionary<int, string> ListToDictionary(List<string> DataList)
        {
            Dictionary<int, string> RetDic = new Dictionary<int, string>();
            for (int i = 0; i < DataList.Count; i++)
            {
                RetDic.Add(i, DataList[i]);
            }

            return RetDic;
        }

        /// <summary>
        /// 将列表转换为字典
        /// </summary>
        public static Dictionary<int, string> ListToDictionary(List<int> DataList)
        {
            Dictionary<int, string> RetDic = new Dictionary<int, string>();
            for (int i = 0; i < DataList.Count; i++)
            {
                RetDic.Add(i + 1, DataList[i].ToString());
            }
            return RetDic;

        }
    }
}

目录

C#-字典(Dictionary)用法