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c#.netnodatime

Get offset minutes from timezone (string) with NodaTime


What's the easiest way to get the minutes if I only have a string that represents the timezone? (for example "Europe/London")

So far I have:

public static int ConvertFromTimeZoneToMinutesOffset(string timeZone)
{
    DateTimeZone zone = DateTimeZoneProviders.Tzdb[timeZone];

    // Need magic code to get offset as minutes
}

But I'm not finding an easy approach to convert it to minutes.

NOTE: What I need is the offset in that specific moment in which the code is being executed. Between that timezone and UTC.


Solution

  • You need DateTimeZone.GetUtcOffset(Instant):

    public static int ConvertFromTimeZoneToMinutesOffset(string timeZone, IClock clock)
    {
        DateTimeZone zone = DateTimeZoneProviders.Tzdb[timeZone];
        Offset offset = zone.GetUtcOffset(clock.Now);
        return offset.Milliseconds / NodaConstants.MillisecondsPerMinute;
    }
    

    You could leave off the IClock parameter and instead use SystemClock.Instance in the method, but that leads to code which is harder to test.