Create datetime object of other timezone in Powers

Question

Basically I am trying to find a way to convert datetime of a particular timezone to other timezone while taking DST into consideration too. e.g.

What is the time in "Central Pacific Standard Time" when it is, say, 2012/9/29 9:00AM in "Tokyo Standard Time" ?

I found some solutions on the Internet to convert local machine time to other timezone.

$ToTimeZoneObj = [system.timezoneinfo]::GetSystemTimeZones() | Where-Object {$_.id -eq $ToTimeZone}
$TargetZoneTime = [system.timezoneinfo]::ConvertTime($datetime, $ToTimeZoneObj)

I am thinking if I can create a datetime object of a timezone different from the local machine, I can then use the solutions I found, or will there be other ways to do what I need?

Thanks

Answer 1

This solution worked well for me:

$cstzone = [System.TimeZoneInfo]::FindSystemTimeZoneById("Central Standard Time")
$csttime = [System.TimeZoneInfo]::ConvertTimeFromUtc((Get-Date).ToUniversalTime(), $cstzone)

You can then manipulate the $csttime variable just like a datetime object:

Get-Date $csttime.AddHours(-1) -f "MM\dd\yyyy HH:mm:ss"

References: http://msdn.microsoft.com/en-us/library/system.timezoneinfo.converttimefromutc(v=vs.110).aspx http://technet.microsoft.com/en-us/library/ee692801.aspx

Answer 2

Working with TimeZones can get pretty tricky. Thank god for the updates they added in .NET 3.5 and 4.0. I worked on several time zone projects and in 2.0 is was nearly impossible without iterating the registry and building your own list of TimeZones.

Now you can get a list of TimeZones by using the TimeZoneInfo class (which you seem to be familiar with): http://msdn.microsoft.com/en-us/library/system.timezoneinfo.aspx

Just beware that a system that may not be updating automatically from Windows Update could potentially have different time zones than a system that is totally up to date. Microsoft pushes out updates for time zones when needed.

I think your code seems OK. To be honest, I'm not much of a PowerShell dev (C# for me), but it seems good.