C# 中的 KeyNotFoundException
csharpprogrammingserver side programming更新于 2025/8/11 22:07:17
当您查找的键在 Dictionary 集合中不存在时，会抛出 KeyNotFoundException 异常。
我们来看一个例子 −
示例
using System;
using System.Collections.Generic;
public class Demo {
public static void Main() {
try {
var dict = new Dictionary<string, string>() {
{"TV", "Electronics"},
{"Laptop", "Computers"},
};
Console.WriteLine(dict["Pen Drive"]);
}
catch (Exception e) {
Console.WriteLine(e);
}
}
}
以下是输出。由于键不在 Dictionary 中，因此错误 KeyNotFoundException 可见 −
输出
System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary. at System.Collections.Generic.Dictionary`2[TKey,TValue].get_Item (TKey key) [0x0001e] in <902ab9e386384bec9c07fa19aa938869>:0
