using System;

using System.Collections.Generic;

using System.Linq;

using TimeZoneConverter; // Ensure you have installed TimeZoneConverter via NuGet

​

class Program

{

    // Method to test

    private static TimeSpan GetUtcOffset(string ianaTz)

    {

        TimeZoneInfo timeZone = TimeZoneInfo.FindSystemTimeZoneById(TimeZoneInfo.GetSystemTimeZones()

            .FirstOrDefault(tz => tz.DisplayName.Contains(ianaTz.Split('/').Last()))?.Id);

​

        return timeZone.BaseUtcOffset;

    }

​

    static void Main(string[] args)

    {

        // Get all IANA time zones

        var ianaTimeZones = TZConvert.KnownIanaTimeZoneNames;

​

        // List to hold errors

        List<string> errors = new List<string>();

​

        // Test each IANA time zone

        foreach (var ianaTz in ianaTimeZones)

        {

            try

            {

                // Get the expected offset using TZConvert

                var windowsTimeZone = TZConvert.IanaToWindows(ianaTz);

                var timeZoneInfo = TimeZoneInfo.FindSystemTimeZoneById(windowsTimeZone);

                var expectedOffset = timeZoneInfo.BaseUtcOffset;

​

                // Get the actual offset using our method

                var actualOffset = GetUtcOffset(ianaTz);

​

                // Check if the offsets match

                if (expectedOffset != actualOffset)

                {

                    errors.Add($"Error: {ianaTz} - Expected: {expectedOffset}, Actual: {actualOffset}");

                }

            }

            catch (Exception ex)

            {

                errors.Add($"Exception for {ianaTz}: {ex.Message}");

            }

        }

​

        // Print errors

        if (errors.Count == 0)

        {

            Console.WriteLine("All tests passed successfully.");

        }

        else

        {

            Console.WriteLine("Errors found:");

            foreach (var error in errors)

            {

                Console.WriteLine(error);

            }

        }

    }

}

​