using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(TimeSpan.FromMinutes(0).DurationFormatted());

        Console.WriteLine(TimeSpan.FromMinutes(5).DurationFormatted());

        Console.WriteLine(TimeSpan.FromMinutes(60).DurationFormatted());

        Console.WriteLine(TimeSpan.FromMinutes(61).DurationFormatted());

        Console.WriteLine(TimeSpan.FromMinutes(164).DurationFormatted());

        Console.WriteLine(TimeSpan.FromMinutes(123).DurationFormatted());

        Console.WriteLine(TimeSpan.FromMinutes(1442).DurationFormatted());

    }

}

​

public static class TimeSpanExtensions 

{

    public static string DurationFormatted(this TimeSpan t) 

    {

        if (t.Days > 0){

            return t.ToString("d'days 'hh'hr 'mm'min'");

        }

        return t.ToString("hh'hr 'mm'min'");

    }

}