一、net4 net core版本

使用LINQ的Contains方法

 string[] array = { "apple", "banana", "cherry" };string key = "banana";bool exists = array.Contains(key);if (exists){Console.WriteLine($"數組中存在鍵 {key}");}else{Console.WriteLine($"數組中不存在鍵 {key}");}

二、通用版本 net2 net4

string[] array = { "apple", "banana", "cherry" };string key = "banana";bool exists = Array.Exists(array, element => element == key);if (exists){Console.WriteLine($"數組中存在鍵 {key}");}else{Console.WriteLine($"數組中不存在鍵 {key}");}}

三、foreach 方法 通用

 string[] array = { "apple", "banana", "cherry" };string key = "banana";bool exists = false;foreach (string item in array){if (item == key){exists = true;break;}}if (exists){Console.WriteLine($"數組中存在鍵 {key}");}else{Console.WriteLine($"數組中不存在鍵 {key}");}}

四、通用js C#

  string[] array = { "apple", "banana", "cherry" };string key = "banana";bool exists = false;for (int i = 0; i < array.Length; i++){if (array[i] == key){exists = true;break;}}if (exists){Console.WriteLine($"數組中存在鍵 {key}");}else{Console.WriteLine($"數組中不存在鍵 {key}");}}