// C# Extension Method

// Doc: https://csharp-extension.com/en/method/1002223/char-notin

​

// @nuget: Z.ExtensionMethods

​

using System;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

        char [] values = {'.','N','E','T','4','.','7','.','2'};

        char input = 'F';

​

        // C# Extension Method: Char - NotIn

        if(input.NotIn(values))

        {

            Console.WriteLine("{0} doesn't exists in the array.", input);

        }

    }

}