// C# Extension Method

// Doc: https://csharp-extension.com/en/method/1002217/char-tolower

​

// @nuget: Z.ExtensionMethods

​

using System;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

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

        Console.WriteLine("Converted all the characters to lower case.");

​

        for (int i = 0; i < input.Length; i++)

        {

            // C# Extension Method: Char - ToLower

            var result = input[i].ToLower();

            Console.WriteLine("{0} : {1} ", input[i], result);

        }

    }

}