TimeSpan.ToFormattedString

public static string ToFormattedString(this TimeSpan value)
        {
            var list = new List<string>(3);

            int days = value.Days;
            int hours = value.Hours;
            int minutes = value.Minutes;
            int seconds = value.Seconds;
            int milliseconds = value.Milliseconds;

            if (days > 1)
                list.Add(String.Format("{0} days", days));
            else if (days == 1)
                list.Add(String.Format("{0} day", days));

            if (hours > 1)
                list.Add(String.Format("{0} hours", hours));
            else if (hours == 1)
                list.Add(String.Format("{0} hour", hours));

            if (minutes > 1)
                list.Add(String.Format("{0} minutes", minutes));
            else if (minutes == 1)
                list.Add(String.Format("{0} minute", minutes));

            if (seconds > 1)
                list.Add(String.Format("{0} seconds", seconds));
            else if (seconds == 1)
                list.Add(String.Format("{0} second", seconds));

            if (milliseconds > 1)
                list.Add(String.Format("{0} ms", milliseconds));
            else if (milliseconds == 1)
                list.Add(String.Format("{0} ms", milliseconds));

            return String.Join(", ", list.ToArray());
        }