C# 程序在 Dictionary 中查找键
csharpprogrammingserver side programming
首先,设置一个包含元素的 Dictionary 集合。
Dictionary<int, string> d = new Dictionary<int, string>() { {1,"Applianes"}, {2, "Clothing"}, {3,"Toys"}, {4,"Footwear"}, {5, "Accessories"} };
现在,假设您需要检查键 5 是否存在。为此,请使用 ContainsKey() 方法。如果找到键,则返回 True。
d.ContainsKey(5);
让我们看一下完整的代码。
示例
using System; using System.Collections.Generic; public class Program { public static void Main() { Dictionary<int, string> d = new Dictionary<int, string>() { {1,"Electronics"}, {2, "Clothing"}, {3,"Toys"}, {4,"Footwear"}, {5, "Accessories"} }; foreach (KeyValuePair<int, string> ele in d) { Console.WriteLine("Key = {0}, Value = {1}", ele.Key, ele.Value); } Console.WriteLine("Key 5 exists? "+d.ContainsKey(5)); } }
输出
Key = 1, Value = Electronics Key = 2, Value = Clothing Key = 3, Value = Toys Key = 4, Value = Footwear Key = 5, Value = Accessories Key 5 exists? True