C# 程序在 Dictionary 中查找键
csharpprogrammingserver side programming更新于 2025/9/13 14:37:00
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
