using System;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

​

        var ids = new string[]

        {

            "America/Detroit",

            "Eastern Standard Time",

            "EST",

             "SomeString"

        };

        var timeZones = TimeZoneInfo.GetSystemTimeZones();

        foreach (var handleTimeZoneAbbreviation in new [] { false, true })

        {

            var abbreviations = handleTimeZoneAbbreviation ?

                new Dictionary<string, string>() { { "est", "America/Atikokan" } } :

                new Dictionary<string, string>();

            foreach (var id in ids)

            {

                var timeZone = timeZones.FirstOrDefault(tz => tz.Id.Equals(id, StringComparison.OrdinalIgnoreCase) || tz.StandardName.Equals(id, StringComparison.OrdinalIgnoreCase));

​

                if (timeZone != null)

                {

                     Console.WriteLine("Found time zone: {0}", timeZone.Id);

                }

                else

                {

                    if (abbreviations.TryGetValue(id.ToLower(), out var timeZoneId))

                    {

                        Console.WriteLine("Found time zone {0} with abbreviations handling equal {1}", timeZoneId, handleTimeZoneAbbreviation);

                    }

                    else

                    {

                        Console.WriteLine("Time zone not found {0} with abbreviations handling equal {1}", id, handleTimeZoneAbbreviation);

                    }

                }

            }

        }

    }

}