using System;

using System.Text;

using Cronos;

public class Program

{

    public static void Main()

    {

        DemoCron("57 0/1 * * *", DateTime.UtcNow);

        DemoCron("57 */1 * * *", DateTime.UtcNow);

        DemoCron("57/1 0/1 * * *", DateTime.UtcNow);

        DemoCron("57/1 */1 * * *", DateTime.UtcNow);

        DemoCron("*/57 0/1 * * *", DateTime.UtcNow);

        DemoCron("*/57 */1 * * *", DateTime.UtcNow);

        //DemoCron("47 0/2 * * *", DateTime.UtcNow);

        //DemoCron("47 0/5 * * *", DateTime.UtcNow);

        //DemoCron("47 0/10 * * *", DateTime.UtcNow);

        //DemoCron("47 0/15 * * *", DateTime.UtcNow);

    }

​

    private static void DemoCron(string cronExpression, DateTime currentTime)

    {

        var cron = CronExpression.Parse(cronExpression);

        var timeZone = TimeZoneInfo.Utc;

        var nextScheduledTime = cron.GetOccurrences(currentTime, currentTime.AddHours(3), timeZone).GetEnumerator();

​

        var ret = new StringBuilder();

        // Print the next scheduled time

        while (nextScheduledTime.MoveNext())

        {

            ret.AppendLine("Next scheduled time: " + nextScheduledTime.Current);

        }

        Console.WriteLine($"Exampling for {cronExpression} @ {currentTime}: \r\n{ret.ToString()}");

    }

}

​