Converting country codes in .NET

Question

In .NET is there any way to convert from three letter country codes (defined in ISO 3166-1 alpha-3) to two letter language codes (defined in ISO 3166-1 alpha-2) eg. convert BEL to BE?

Have looked at the RegionInfo class in System.Globalization but the constructor does not seem to support the three letter codes.

Answer 1

The RegionInfo class does know the three-letter code (in the ThreeLetterISORegionName property), but I don’t think there is a way to get RegionInfo based on this code, you would need to enumerate all regions and add them to your own dictionary, with the three-letter code as a key.

However, I think the .NET Framework uses RegionInfo to work with cultures, not countries in the ISO 3166-1 sense. Therefore, many countries from the ISO 3166-1 standard are not available (try e.g. SX). I guess you should create your own country codebook.

Edit: From 246 countries in my current country codebook, RegionInfo is available for 125 of them, the rest (121) are not supported. Conclusion: This is not a good way to get a country codebook.

Answer 2

Looks like there is no built-in way to do that. You can use the approach from the GenericTypeTea's answer. But if you need to convert many country codes you can avoid Cultures enumeration and pre-compute a mapping dictionary for country codes conversion.

That's how such generator looks like:

namespace ISOCountryCodes {     using System;     using System.Collections.Generic;     using System.Globalization;     using System.Linq;      class Program     {         public static void Main(string[] args)         {             var countryCodesMapping = new Dictionary<string, RegionInfo>();             CultureInfo[] cultures = CultureInfo.GetCultures(CultureTypes.SpecificCultures);              foreach (var culture in cultures)             {                 try                 {                     var region = new RegionInfo(culture.LCID);                     countryCodesMapping[region.ThreeLetterISORegionName] = region;                 }                 catch (CultureNotFoundException)                 {                     var consoleColor = Console.ForegroundColor;                      Console.ForegroundColor = ConsoleColor.Red;                     Console.WriteLine("Culture not found: " + culture.Name);                     Console.ForegroundColor = consoleColor;                 }             }              Console.WriteLine("var countryCodesMapping = new Dictionary<string, string>() {");             foreach (var mapping in countryCodesMapping.OrderBy(mapping => mapping.Key))             {                 Console.WriteLine("   {{ \"{0}\", \"{1}\" }},    // {2}", mapping.Key, mapping.Value.TwoLetterISORegionName, mapping.Value.EnglishName);             }              Console.WriteLine("};");         }     } } 

Run this generator to get a country codes mapping dictionary like this:

var countryCodesMapping = new Dictionary<string, string>() {    { "AFG", "AF" },    // Afghanistan    { "ALB", "AL" },    // Albania    { "ARE", "AE" },    // U.A.E.    { "ARG", "AR" },    // Argentina    { "ARM", "AM" },    // Armenia    { "AUS", "AU" },    // Australia    { "AUT", "AT" },    // Austria    { "AZE", "AZ" },    // Azerbaijan    { "BEL", "BE" },    // Belgium    { "BGD", "BD" },    // Bangladesh    { "BGR", "BG" },    // Bulgaria    { "BHR", "BH" },    // Bahrain    { "BIH", "BA" },    // Bosnia and Herzegovina    { "BLR", "BY" },    // Belarus    { "BLZ", "BZ" },    // Belize    { "BOL", "BO" },    // Bolivia    { "BRA", "BR" },    // Brazil    { "BRN", "BN" },    // Brunei Darussalam    { "CAN", "CA" },    // Canada    { "CHE", "CH" },    // Switzerland    { "CHL", "CL" },    // Chile    { "CHN", "CN" },    // People's Republic of China    { "COL", "CO" },    // Colombia    { "CRI", "CR" },    // Costa Rica    { "CZE", "CZ" },    // Czech Republic    { "DEU", "DE" },    // Germany    { "DNK", "DK" },    // Denmark    { "DOM", "DO" },    // Dominican Republic    { "DZA", "DZ" },    // Algeria    { "ECU", "EC" },    // Ecuador    { "EGY", "EG" },    // Egypt    { "ESP", "ES" },    // Spain    { "EST", "EE" },    // Estonia    { "ETH", "ET" },    // Ethiopia    { "FIN", "FI" },    // Finland    { "FRA", "FR" },    // France    { "FRO", "FO" },    // Faroe Islands    { "GBR", "GB" },    // United Kingdom    { "GEO", "GE" },    // Georgia    { "GRC", "GR" },    // Greece    { "GRL", "GL" },    // Greenland    { "GTM", "GT" },    // Guatemala    { "HKG", "HK" },    // Hong Kong S.A.R.    { "HND", "HN" },    // Honduras    { "HRV", "HR" },    // Croatia    { "HUN", "HU" },    // Hungary    { "IDN", "ID" },    // Indonesia    { "IND", "IN" },    // India    { "IRL", "IE" },    // Ireland    { "IRN", "IR" },    // Iran    { "IRQ", "IQ" },    // Iraq    { "ISL", "IS" },    // Iceland    { "ISR", "IL" },    // Israel    { "ITA", "IT" },    // Italy    { "JAM", "JM" },    // Jamaica    { "JOR", "JO" },    // Jordan    { "JPN", "JP" },    // Japan    { "KAZ", "KZ" },    // Kazakhstan    { "KEN", "KE" },    // Kenya    { "KGZ", "KG" },    // Kyrgyzstan    { "KHM", "KH" },    // Cambodia    { "KOR", "KR" },    // Korea    { "KWT", "KW" },    // Kuwait    { "LAO", "LA" },    // Lao P.D.R.    { "LBN", "LB" },    // Lebanon    { "LBY", "LY" },    // Libya    { "LIE", "LI" },    // Liechtenstein    { "LKA", "LK" },    // Sri Lanka    { "LTU", "LT" },    // Lithuania    { "LUX", "LU" },    // Luxembourg    { "LVA", "LV" },    // Latvia    { "MAC", "MO" },    // Macao S.A.R.    { "MAR", "MA" },    // Morocco    { "MCO", "MC" },    // Principality of Monaco    { "MDV", "MV" },    // Maldives    { "MEX", "MX" },    // Mexico    { "MKD", "MK" },    // Macedonia (FYROM)    { "MLT", "MT" },    // Malta    { "MNE", "ME" },    // Montenegro    { "MNG", "MN" },    // Mongolia    { "MYS", "MY" },    // Malaysia    { "NGA", "NG" },    // Nigeria    { "NIC", "NI" },    // Nicaragua    { "NLD", "NL" },    // Netherlands    { "NOR", "NO" },    // Norway    { "NPL", "NP" },    // Nepal    { "NZL", "NZ" },    // New Zealand    { "OMN", "OM" },    // Oman    { "PAK", "PK" },    // Islamic Republic of Pakistan    { "PAN", "PA" },    // Panama    { "PER", "PE" },    // Peru    { "PHL", "PH" },    // Republic of the Philippines    { "POL", "PL" },    // Poland    { "PRI", "PR" },    // Puerto Rico    { "PRT", "PT" },    // Portugal    { "PRY", "PY" },    // Paraguay    { "QAT", "QA" },    // Qatar    { "ROU", "RO" },    // Romania    { "RUS", "RU" },    // Russia    { "RWA", "RW" },    // Rwanda    { "SAU", "SA" },    // Saudi Arabia    { "SCG", "CS" },    // Serbia and Montenegro (Former)    { "SEN", "SN" },    // Senegal    { "SGP", "SG" },    // Singapore    { "SLV", "SV" },    // El Salvador    { "SRB", "RS" },    // Serbia    { "SVK", "SK" },    // Slovakia    { "SVN", "SI" },    // Slovenia    { "SWE", "SE" },    // Sweden    { "SYR", "SY" },    // Syria    { "TAJ", "TJ" },    // Tajikistan    { "THA", "TH" },    // Thailand    { "TKM", "TM" },    // Turkmenistan    { "TTO", "TT" },    // Trinidad and Tobago    { "TUN", "TN" },    // Tunisia    { "TUR", "TR" },    // Turkey    { "TWN", "TW" },    // Taiwan    { "UKR", "UA" },    // Ukraine    { "URY", "UY" },    // Uruguay    { "USA", "US" },    // United States    { "UZB", "UZ" },    // Uzbekistan    { "VEN", "VE" },    // Bolivarian Republic of Venezuela    { "VNM", "VN" },    // Vietnam    { "YEM", "YE" },    // Yemen    { "ZAF", "ZA" },    // South Africa    { "ZWE", "ZW" },    // Zimbabwe };