C＃中的ContainsKey

一、ContainsKey

• ContainsKey是C＃中的Dictionary方法，用于检查Dictionary中是否存在键。

1、 声明字典并添加元素

var dict = new Dictionary<string, int>() {
   {"TV", 1},
   {"Home Theatre", 2},
   {"Amazon Alexa", 3},
   {"Google Home", 5},
   {"Laptop", 5},
   {"Bluetooth Speaker", 6}
};

2、检查字典中是否存在特定元素

if (dict.ContainsKey("Laptop") == true) {
   Console.WriteLine(dict["Laptop"]);
}

3、代码

using System;
using System.Collections.Generic;
public class Demo {
   public static void Main() {
      var dict = new Dictionary<string, int>() {
         {"TV", 1},
         {"Home Theatre", 2},
         {"Amazon Alexa", 3},
         {"Google Home", 5},
         {"Laptop", 5},
         {"Bluetooth Speaker", 6}
      };
      if (dict.ContainsKey("Laptop") == true) {
         Console.WriteLine(dict["Laptop"]);
      }
      if (dict.ContainsKey("Amazon Alexa") == true) {
         Console.WriteLine(dict["Amazon Alexa"]);
      }
   }
}

输出量

5
3

二、资料

码农家园： https://www.codenong.com/containskey-in-chash/