如何获取ISO8601定义的Work Week

using System;
using System.Globalization;

namespace MACAddressMgmtApp.ServiceImplementations
{
    public static class WorkWeekHelper
    {

        public static int GetIso8601WeekOfYear(DateTime dt)
        {
            
            DayOfWeek day = CultureInfo.InvariantCulture.Calendar.GetDayOfWeek(dt);

            if (day >= DayOfWeek.Monday && day <= DayOfWeek.Wednesday)
            {

                dt = dt.AddDays(3);

            }

            return CultureInfo.InvariantCulture.Calendar.GetWeekOfYear(dt, CalendarWeekRule.FirstFourDayWeek, DayOfWeek.Monday);

        }

    }

}