Country name to ISO 3166-2 code

Question

I know how to convert an ISO 3166-2 code to the full English name, e.g. "US" to "United States" by using RegionInfo.

However, how can I do the opposite, i.e. that takes "United States" and returns "US"?

Answer 1

//Get the cultureinfo
RegionInfo rInfo = new RegionInfo("us");
string s = rInfo.EnglishName;

//Convert it back
CultureInfo[] cultures = CultureInfo.GetCultures(CultureTypes.SpecificCultures);
 CultureInfo cInfo = cultures.FirstOrDefault(culture => new RegionInfo(culture.LCID).EnglishName == s);

Answer 2

The main idea: take all region objects and select from them one which contains given full name.

var regionFullNames = CultureInfo
                      .GetCultures( CultureTypes.SpecificCultures )
                      .Select( x => new RegionInfo(x.LCID) )
                      ;
var twoLetterName = regionFullNames.FirstOrDefault(
                       region => region.EnglishName.Contains("United States")
                    );