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TimeZoneNames NuGet Version

A simple library that provides localized time zone names using CLDR and TZDB sources.

Why? Because .NET's usual time zone display names are not localized properly, and are often wrong or unsuitable for various scenarios. Read this blog post for more details.

Nuget Installation

PM> Install-Package TimeZoneNames

This library should be compatible with .NET Standard 1.1 and greater, as well as .NET Framework 3.5 and greater. See the .NET Standard Platform Support Matrix for further details about .NET Standard, and please raise an issue if you encounter any compatibility errors.

Demo

One possible scenario for this library is to build a localized time zone selection control. Click here for a live demonstration.

Usage

First, import the TimeZoneNames namespace:

using TimeZoneNames;

All functionality is provided as static methods from the TZNames class.

Methods for localizing a single time zone

GetNamesForTimeZone

Look up the localized names for a specific time zone:

var names = TZNames.GetNamesForTimeZone("America/Los_Angeles", "en-US");

names.Generic == "Pacific Time"
names.Standard == "Pacific Standard Time"
names.Daylight == "Pacific Daylight Time"
var names = TZNames.GetNamesForTimeZone("America/Los_Angeles", "fr-CA");

names.Generic == "heure du Pacifique"
names.Standard == "heure normale du Pacifique"
names.Daylight == "heure avancée du Pacifique"

You can pass a Windows time zone id instead, if you like:

var names = TZNames.GetNamesForTimeZone("Romance Standard Time", "en-GB");

names.Generic == "Central European Time"
names.Standard == "Central European Standard Time"
names.Daylight == "Central European Summer Time"

GetAbbreviationsForTimeZone

Look up the localized abbreviations for a specific time zone:

var abbreviations = TZNames.GetAbbreviationsForTimeZone("America/Los_Angeles", "en-US");

abbreviations.Generic == "PT"
abbreviations.Standard == "PST"
abbreviations.Daylight == "PDT"

You can pass a Windows time zone id instead, if you like:

var abbreviations = TZNames.GetAbbreviationsForTimeZone("Romance Standard Time", "en-GB");

names.Generic == "CET"
abbreviations.Standard == "CET"
abbreviations.Daylight == "CEST"

Note: Time zone abbreviations are sometimes inconsistent, and are not necessarily localized correctly for every time zone. In most cases, you should use abbreviations for end-user display output only. Do not attempt to use abbreviations when parsing input.

Methods for listing time zones

GetDisplayNames

Gets a dictionary of string/string pairs of time zones, where the key is a time zone identifier, and the value is the localized name of the time zone, as given by the Windows language pack for the specified language and locale.

This is useful because the values returned by TimeZoneInfo.DisplayName are only localized by the operating system's language, whereas TZNames.GetDisplayNames will work with any supported language.

var displayNames = TZNames.GetDisplayNames("fr-CA");

Output

Key Value
Dateline Standard Time (UTC-12:00) Ligne de date internationale (Ouest)
UTC-11 (UTC-11:00) Temps universel coordonné-11
Aleutian Standard Time (UTC-10:00) Îles Aléoutiennes
Hawaiian Standard Time (UTC-10:00) Hawaii
Marquesas Standard Time (UTC-09:30) Îles Marquises
Alaskan Standard Time (UTC-09:00) Alaska
UTC-09 (UTC-09:00) Temps universel coordonné-09
Pacific Standard Time (Mexico) (UTC-08:00) Basse Californie
UTC-08 (UTC-08:00) Temps universel coordonné-08
Pacific Standard Time (UTC-08:00) Pacifique (É.-U. et Canada)
... ...

Optionally, you can pass true as a second parameter to return IANA time zone IDs as the keys, though the list will still be limited to valid Windows time zones. When doing so, if there is a country code in the locale (eg. the CA in fr-CA) that code will be used as the territory code in the Windows to IANA mapping.

GetTimeZonesForCountry

Gets a list of time zone names for a specific country, suitable for user time zone selection.

Returns a dictionary whose key is the IANA time zone identifier, and whose value is the localized generic time zone name. When more than one entry in the result set shares the same name, then a localized city name is appended in parenthesis to disambiguate. (This is usually due to historical differences.)

var zones = TZNames.GetTimeZonesForCountry("BR", "pt-BR");

Output

Key Value
America/Eirunepe Horário do Acre (Eirunepé)
America/Rio_Branco Horário do Acre (Rio Branco)
America/Porto_Velho Horário do Amazonas (Porto Velho)
America/Boa_Vista Horário do Amazonas (Boa Vista)
America/Manaus Horário do Amazonas (Manaus)
America/Campo_Grande Horário do Amazonas (Campo Grande)
America/Cuiaba Horário do Amazonas (Cuiabá)
America/Belem Horário de Brasília (Belém)
America/Fortaleza Horário de Brasília (Fortaleza)
America/Recife Horário de Brasília (Recife)
America/Araguaina Horário de Brasília (Araguaína)
America/Maceio Horário de Brasília (Maceió)
America/Bahia Horário de Brasília (Bahia)
America/Santarem Horário de Brasília (Santarém)
America/Sao_Paulo Horário de Brasília (São Paulo)
America/Noronha Horário de Fernando de Noronha

Many scenarios don't require all time zones, so you can specify a threshold date as an optional parameter:

var zones = TZNames.GetTimeZonesForCountry("BR", "pt-BR", new DateTime(2010, 1, 1));

Output

Key Value
America/Rio_Branco Horário do Acre
America/Manaus Horário do Amazonas (Manaus)
America/Cuiaba Horário do Amazonas (Cuiabá)
America/Fortaleza Horário de Brasília (Fortaleza)
America/Araguaina Horário de Brasília (Araguaína)
America/Bahia Horário de Brasília (Bahia)
America/Sao_Paulo Horário de Brasília (São Paulo)
America/Noronha Horário de Fernando de Noronha

If you are not concerned with historical time zone differences at all, then pass DateTimeOffset.UtcNow to return only time zones that differ in the future.

var zones = TZNames.GetTimeZonesForCountry("BR", "pt-BR", DateTimeOffset.UtcNow);

Output

Key Value
America/Rio_Branco Horário do Acre
America/Manaus Horário do Amazonas (Manaus)
America/Cuiaba Horário do Amazonas (Cuiabá)
America/Bahia Horário de Brasília (Bahia)
America/Sao_Paulo Horário de Brasília (São Paulo)
America/Noronha Horário de Fernando de Noronha

GetTimeZoneIdsForCountry

Get a list of time zone identifiers for a specific country. Similar to the GetTimeZonesForCountry method, but without localized names.

string[] zones = TZNames.GetTimeZoneIdsForCountry("AU");

Output

Australia/Perth
Australia/Eucla
Australia/Darwin
Australia/Broken_Hill
Australia/Adelaide
Australia/Brisbane
Australia/Lindeman
Australia/Hobart
Australia/Currie
Australia/Melbourne
Australia/Sydney
Australia/Lord_Howe
Antarctica/Macquarie

Like the GetTimeZonesForCountry method, an optional threshold parameter is supported for limiting the list to those zones that vary only after a specific date.

string[] zones = TZNames.GetTimeZoneIdsForCountry("AU", DateTimeOffset.Now);

Output

Australia/Perth
Australia/Eucla
Australia/Darwin
Australia/Adelaide
Australia/Brisbane
Australia/Sydney
Australia/Lord_Howe
Antarctica/Macquarie

GetFixedTimeZoneIds

Gets a list of time zone IDs that represent fixed offset from UTC, including UTC itself. Note that time zones of the form Etc/GMT[+/-]n use an inverted sign from the usual conventions.

TODO: Add examples for this method.

GetFixedTimeZoneNames

Gets the same list of zones as GetFixedTimeZoneIds, but includes localized names.

TODO: Add examples for this method.

GetFixedTimeZoneAbbreviations

Gets the same list of zones as GetFixedTimeZoneIds, but includes localized abbreviations.

TODO: Add examples for this method.

Additional supporting methods

GetDisplayNameForTimeZone

string displayName = TZNames.GetDisplayNameForTimeZone("America/Vancouver", "fr");
// => "(UTC-08:00) Pacifique (É.-U. et Canada)"
string displayName = TZNames.GetDisplayNameForTimeZone("India Standard Time", "zh-CN");
// => "(UTC+05:30) 钦奈，加尔各答，孟买，新德里"

GetCountryNames

Gets a localized list of country names, suitable for selecting a country before selecting a time zone in a two-dropdown time zone selection control.

var countries = TZNames.GetCountryNames("en-GB");

Output

Key Value
AF Afghanistan
AX Åland Islands
AL Albania
.. ...
YE Yemen
ZM Zambia
ZW Zimbabwe

GetLanguageCodes

Gets a list of all language codes supported by this library. Useful for testing and validation.

var languages = TZNames.GetLanguageCodes();

Output

af
agq
ak
am
ar
ar_ae
...
zgh
zh
zh_hans_sg
zh_hant
zh_hant_hk
zu

Acknowledgements

Many thanks to Tom Kludy, who helped figure out how to extract localized display names from Windows language packs. This library uses output from his TimeZoneWindowsResourceExtractor to enable the GetDisplayNames and GetDisplayNameForTimeZone methods.