using System;

using System.Globalization;

using EWSoftware.PDI;

​

public class Program

{

    public static String StringBetween(String str, String strFrom, String strTo)

    {

        int pFrom = str.IndexOf(strFrom) + strFrom.Length;

        int pTo = str.LastIndexOf(strTo);

        return str.Substring(pFrom, pTo - pFrom);

    }

​

    public static void Main()

    {

        string rrule = "DTSTART:20190729T230000Z\nRRULE:FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR,SA,SU;UNTIL=20190730T205959Z";

        string timezone = "Pacific Standard Time";

        TimeZoneInfo tz = TimeZoneInfo.FindSystemTimeZoneById(TimeZoneConverter.TZConvert.WindowsToIana(timezone));

        DateTime start = TimeZoneInfo.ConvertTimeFromUtc(DateTime.ParseExact(StringBetween(rrule, "DTSTART:", "\nRRULE:"), "yyyyMMdd'T'HHmmss'Z'", CultureInfo.InvariantCulture, DateTimeStyles.None), tz);

        DateTime until = TimeZoneInfo.ConvertTimeFromUtc(DateTime.ParseExact(StringBetween(rrule, "UNTIL=", "Z"), "yyyyMMdd'T'HHmmss", CultureInfo.InvariantCulture, DateTimeStyles.None), tz);

        if (until.TimeOfDay < start.TimeOfDay)

            until = until.AddDays(1);

        DateTime end = DateTime.Parse(start.ToShortDateString() + " " + until.ToShortTimeString());

        if (end < start)

            end = end.AddDays(1);

        DateTime today = TimeZoneInfo.ConvertTimeFromUtc(DateTime.UtcNow, tz);

        Recurrence recur = new Recurrence(StringBetween(rrule, "\nRRULE:", ""));

        recur.StartDateTime = start;

        recur.RecurUntil = until;

        Console.WriteLine(recur.ToDescription());

        Console.WriteLine("It is currently " + today);

        Console.WriteLine("Start on " + start);

        Console.WriteLine("Until " + until);

        Console.WriteLine("End on  " + end);

        if (recur.OccursOn(today, false) && today >= start && today < end)

        {

            Console.WriteLine("Ad is scheduled");

        }

        else

        {

            Console.WriteLine("Ad is NOT scheduled");

        }

    }

}