TimeSpan-ToConciseString.cs

using System;
using System.Collections.Generic;
using System.Text;

namespace tests
{
    public static class ExtensionMethods
    {
        /// <summary>
        /// Returns the TimeSpan text in a concise way 
        /// using at most two of the DateTime components.
        /// </summary>
        /// <returns>
        /// Example Return Strings
        /// 2 days and 4 hours ago
        /// 1 day ago (if hours are zero)
        /// 1 hour abd 14 minutes ago
        /// 25 minutes and 15 seconds ago
        /// 30 seconds ago (if minutes are zero)
        /// </returns>
        public static string ToConciseString(this TimeSpan timeSpan)
        {
            if (timeSpan.TotalMilliseconds == 0)
            {
                return "just now";
            }

            List<string> s = new List<string>();
            if (timeSpan.Days == 1) s.Add($"{timeSpan.Days} day");
            if (timeSpan.Days > 1) s.Add($"{timeSpan.Days} days");

            if (timeSpan.Hours == 1) s.Add($"{timeSpan.Hours} hour");
            if (timeSpan.Hours > 1) s.Add($"{timeSpan.Hours} hours");

            if (timeSpan.Days < 1)
            {
                if (timeSpan.Minutes == 1) s.Add($"{timeSpan.Minutes} minute");
                if (timeSpan.Minutes > 1) s.Add($"{timeSpan.Minutes} minutes");

                if (timeSpan.Hours < 1)
                {
                    if (timeSpan.Seconds == 1) s.Add($"{timeSpan.Seconds} second");
                    if (timeSpan.Seconds > 1) s.Add($"{timeSpan.Seconds} seconds");

                    if (timeSpan.Minutes < 1)
                    {
                        if (timeSpan.Milliseconds == 1) s.Add($"{timeSpan.Milliseconds} millisecond");
                        if (timeSpan.Milliseconds > 1) s.Add($"{timeSpan.Milliseconds} milliseconds");
                    }
                }
            }

            return string.Join(" and ", s) + " ago";
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine(new TimeSpan(2, 5, 45, 30, 800).ToConciseString());
            Console.WriteLine(new TimeSpan(2, 1, 45, 30, 800).ToConciseString());
            Console.WriteLine(new TimeSpan(1, 5, 45, 30, 800).ToConciseString());
            Console.WriteLine(new TimeSpan(0, 5, 45, 30, 800).ToConciseString());
            Console.WriteLine(new TimeSpan(0, 0, 45, 30, 800).ToConciseString());
            Console.WriteLine(new TimeSpan(0, 0, 0, 30, 800).ToConciseString());
            Console.WriteLine(new TimeSpan(0, 0, 0, 0, 800).ToConciseString());
            Console.WriteLine(new TimeSpan(0, 0, 0, 0, 0).ToConciseString());
        }
    }
}