Current date time in specific timezone with and without DST offset with NodaTime

I need to sync a device internal clock on a device according to which timezone the users has selected. I'm using the following code to get the current time for that zone with respect to the system clock: 

var currentInstant = SystemClock.Instance.GetCurrentInstant().InZone(userTimezone);

But I also need to be able to toggle a flag that enables/disables DST for the zone, meaning if the zone currently has DST active I need to be able to subtract the offset it adds, and only set the internal clock to the zone time with the standard offset.

I found the standard offset with (not 100% this is correct though):

currentInstant.GetZoneInterval().StandardOffset;

But I'm not sure how to get the zone time using it?

Jon Skeet
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It sounds like you're nearly there. You presumably want the OffsetDateTime or LocalDateTime, which you'd get like this:

var now = SystemClock.Instance.GetCurrentInstant();
var zoneInterval = zone.GetZoneInterval(now);
var offset = zoneInterval.StandardOffset; // Ignore any savings
OffsetDateTime offsetNow = now.WithOffset(offset);

You can get the LocalDateTime with offsetNow.LocalDateTime if you need that.

At that point, you don't have a ZonedDateTime, because you don't really have a time zone as such - your "zone without DST" isn't a regular time zone. But it sounds like it's what you need.

As Matt said, this is a fundamentally bad idea - I know you've tried to convince your client of that already, but it's probably worth thinking ahead and working out what you'll do when your client understands that it's a bad idea too...

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