Question

Is there anyway to create an instance of cultureInfo object using the full displayname:

CultureInfo userCulture = new CultureInfo("Japanese (Japan)");

or convert the full displayname to culture code:

toCultureCode("Japanese (Japan)"); 

would return "ja-JP"

Answer 1

There’s no builtin method to get a culture by it’s english name, so you could write one:

public static CultureInfo getCultureByEnglishName(String englishName)
{
    // create an array of CultureInfo to hold all the cultures found, 
    // these include the users local culture, and all the
    // cultures installed with the .Net Framework
    CultureInfo[] cultures = CultureInfo.GetCultures(CultureTypes.AllCultures & ~CultureTypes.NeutralCultures);
    // get culture by it's english name 
    var culture = cultures.FirstOrDefault(c => 
        c.EnglishName.Equals(englishName, StringComparison.InvariantCultureIgnoreCase));
    return culture;
}

DEMO

The toCultureCode is ToString:

String name = "Japanese (Japan)";
CultureInfo japanCulture = getCultureByEnglishName(name);
Console.Write(japanCulture.ToString()); // -> "ja-JP"