Basing on this question i would like to convert a users' nationality selected from a combobox to it's two letter country code. If a user selects "South Africa" as their country i need to convert it to "SA". I tried the code below and it throw a nullreference exception.
var regions = CultureInfo.GetCultures(CultureTypes.SpecificCultures).Select(x => new RegionInfo(x.LCID));
var english_region = regions.FirstOrDefault(region => region.EnglishName == this.Nationality);
string code = english_region.TwoLetterISORegionName;