using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        FiddleHelper.WriteTable(GetDates(2023,3));

    }

    public static List<String> GetDates(int year, int month)

    {

       return Enumerable.Range(1, DateTime.DaysInMonth(year, month))  // Days: 1, 2 ... 31 etc.

                        .Select(day => new DateTime(year, month, day).ToLongDateString()) // Map each day to a date

                        .ToList(); // Load dates into a list

    }

}

​