I have tried searching informations on net.core documentation (issue etc) without results.
The code is simpler:
[HttpGet()]
[Route("dob")]
public string dobTest()
{
var content = #"""1942-01-01T22:00:00.000Z""";
var settings = new JsonSerializerSettings()
{
//DateFormatHandling = DateFormatHandling.IsoDateFormat,
//DateParseHandling = DateParseHandling.DateTimeOffset,
DateTimeZoneHandling = DateTimeZoneHandling.Local,
//DateTimeZoneHandling = DateTimeZoneHandling.RoundtripKind
};
var dob = JsonConvert.DeserializeObject<DateTime>(content, settings);
return $"dob: {dob.ToString("yyyy-MM-dd HH:mm:ss.fff")} - {dob.Kind}";
}
if I run this code on Mac or Linux the result is:
dob: 1942-01-02 00:00:00.000 - Local
if I run this code on windows the result is:
dob: 1942-01-01 23:00:00.000 - Local
My MacOs timezone is set on Rome(UTC +01:00)
Windows timezone is set on Rome(UTC +01:00)
the version of Newtonsoft.Json is 12.0.3
The version of net framework is net core 3.1
Linux and OSX both use the IANA time zone database for its primary source of time zone information, which has correct historical data for time zones in 1942 in Rome, under the identifier Europe/Rome. You can see that UTC+2 is the correct offset for the date given here as well.
Windows, on the other hand, does not have that history for this time zone. The equivalent Windows identifier is W. Europe Standard Time, which has an English display name of (UTC+01:00) Amsterdam, Berlin, Bern, Rome, Stockholm, Vienna. You can see the data Windows has in the registry under the following key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones\W. Europe Standard Time
If you examine this key using RegEdit, you'll notice that unlike several other time zones, there is no Dynamic DST subkey for this zone. That means Windows is not aware of any historical differences in DST rules, and thus treats every year the under the same set of rules.
Windows does have historical data for some zones, but in general Microsoft only guarantees historical accuracy since 2010 per its DST/TZ support policy.
Thus, if you have the need in your application for historical time zone accuracy, then you should use IANA time zones only. In .NET, you can do this by using TZDB provider in the Noda Time library.
Related
This question already has answers here:
TimeZoneInfo in .NET Core when hosting on unix (nginx)
(8 answers)
Closed 1 year ago.
I have deployed my asp.net core application in azure linux. I am trying to convert UTC time to 'Central Europe Standard Time'.
But, I am getting the following exception. In my local no issues, but I am getting issue after deployment.
The time zone ID 'Central Europe Standard Time' was not found on the
local computer. Could not find file '/usr/share/zoneinfo/Central
Europe Standard Time'.
TimeZoneInfo cstZone = TimeZoneInfo.FindSystemTimeZoneById("Central Europe Standard Time");
var cstTime = TimeZoneInfo.ConvertTimeFromUtc(utcDateTime, cstZone);
For the App Services that run on Linux, you should use Time Zone values from the IANA TZ database.
In your case Time Zone Central Europe Standard Time in linux could be Europe/Amsterdam
https://en.wikipedia.org/wiki/List_of_tz_database_time_zones
https://learn.microsoft.com/en-us/azure/app-service/faq-configuration-and-management#how-do-i-set-the-server-time-zone-for-my-web-app
Linux and Windows store timzones differently (see for example TimeZoneInfo in .NET Core when hosting on unix (nginx)).
One solution is to examine what is available and choose appropriately like shown at How to get TimeZoneInfo on Windows and Linux from www.ankursheel.com:
var nzTimeZone = TimeZoneInfo.GetSystemTimeZones().Any(x => x.Id == "New Zealand Standard Time")
? TimeZoneInfo.FindSystemTimeZoneById("New Zealand Standard Time")
: TimeZoneInfo.FindSystemTimeZoneById("Pacific/Auckland");
I have a transaction date stored in the database as DateTimeOffset UtcNow.
When I retrieve the date, I get something like the following
16/08/2020 9:12:34 PM +00:00
But I want to represent the time of transaction to represent the exact time in the timezone of UTC+1 which is where my client resides. But when I try to use the following code
TimeZoneInfo.ConvertTime(item.TransactionTime, TimeZoneInfo.FindSystemTimeZoneById("W. Central Africa Standard Time"));
I get the following error,
TimeZoneNotFoundException: The time zone ID 'UTC+1' was not found on the local computer.
I have also tried
TimeZoneInfo.ConvertTime(item.TransactionTime, TimeZoneInfo.FindSystemTimeZoneById("West Central Africa"));
Yet no luck.
What could I be getting wrong?
My application is on ASP.NET-Core 3.1 running on windows server.
Please help
TimeZoneInfo NaijaZone = TimeZoneInfo.FindSystemTimeZoneById("W. Central Africa Standard Time");
I got it working using the code up there, although it was writing that error above as well but I think whitespace affected the ID.
I am looking into mapping a location such as an adress to a Windows TimeZone format. For instance if the address contains the Copenhagen city, then the service should map it to (UTC+01:00) Brussels, Copenhagen, Madrid, Paris.
If the address contains a city close to Vienna then it should map it to (UTC+01:00) Amsterdam, Berlin, Bern, Rome, Stockholm, Vienna.
I have looked into Google's GeoCoding and TimeZone APIs, but it only gives me the name of the timezone like "Central European Time".
This is a multi-step process:
Determine the location's latitude and longitude coordinates.
You mentioned Google's geocoding API. That will do fine, and there are several others to choose from.
Determine the time zone identifier from those coordinates using any of these methods.
In most cases, you'll receive an IANA time zone identifier, such as "Europe/Vienna". You mentioned the Google time zone API - which returns this value in the timeZoneId field (not timeZoneName).
Use the IANA time zone identifier to obtain a .NET TimeZoneInfo object.
If you are running .NET on a non-Windows platform (Linux, OSX, etc.) you can obtain a TimeZoneInfo object directly from the IANA time zone identifier:
// This will work on platforms that use IANA time zones natively
TimeZoneInfo tzi = TimeZoneInfo.FindSystemTimeZoneById("Europe/Vienna");
If you are running .NET on Windows, or want to write your application to run on any platform, then use my TimeZoneConverter library to retrieve the TimeZoneInfo object:
// This will work on any platform
TimeZoneInfo tzi = TZConvert.GetTimeZoneInfo("Europe/Vienna");
If you actually need a Windows time zone identifier, then TimeZoneConverter can do that as well:
string tz = TZConvert.IanaToWindows("Europe/Vienna");
//=> "W. Europe Standard Time"
Separately, if you want to get the actual string "(UTC+01:00) Amsterdam, Berlin, Bern, Rome, Stockholm, Vienna", then:
If on Windows, and the Windows OS locale is English, then you can just get .DisplayName from the TimeZoneInfo object.
In all other cases, you can skip step 3 above and just use my TimeZoneNames library, which has all display names for all languages:
string displayName = TZNames.GetDisplayNameForTimeZone("Europe/Vienna", "en");
Also, you might consider using NodaTime instead of a TimeZoneInfo object.
From yesterday (the first day of US day light saving adjustment had began.) the same code that runs on two different computers are giving different results. Here are the code:
DateTime t = TimeZoneInfo.ConvertTimeBySystemTimeZoneId(
DateTime.UtcNow, r.timeZone);
While timezone used here is "US Eastern Standard Time"
Input (DateTime.UtcNow) is 2012/03/13 19:10:00
On a windows XP SP3 machine the code returns: 2012/03/13 14:10:00
On a windows server 2008 machine the same code returns: 2012/03/13 15:10:00
This is not expected. Any thoughts?
Best.
The current time zone on the XP machine is "US Eastern Standard Time" while the current time zone on the Server machine is "US Eastern Daylight Time". The US changed from Standard to Daylight time on Sunday. Perhaps the XP machine needs to have its time zone information updated.
The TimeZoneInfo.Id property appears to be unsupported on Windows Phone. How can I access the official time zone (TZ) identifier on Windows Phone? For example, "America/Los_Angeles".
The TimeZoneInfo.StandardName property returns "Pacific Standard Time", which is not the TZ identifier. Thank you.
Windows Phone 7 does not provide TZ values directly, for example through the TimeZoneInfo class. You could use the ZoneInfo (tz Database / Olson Database) .NET API to look up the TZ value.