Find Cultureinfo and RegionInfo from browser in ASP.NET

Get language and country from a browser in ASP.NET by Mads Kristensen

I recently had the challenge of retrieving a country based on the browser language. It was used to pre-select a country in a drop down list so the user didn’t have to. I knew it wasn’t going to be 100% accurate but probably more like 80-90%.

That’s because some people change the browser language instead of their native language and others use a non-ISO standard language. And last, some clients just don’t send language information.

It wasn’t an option to use a database that mapped IP addresses to countries, so the country had to be resolved from the browser alone.

Resolve the culture

I decided to split the functionality up into two methods. The first one resolves the CultureInfo based on the browsers language.

 

public static CultureInfo ResolveCulture()

{

  string[] languages = HttpContext.Current.Request.UserLanguages;

 

  if (languages == null || languages.Length == 0)

    return null;

 

  try

  {

    string language = languages[0].ToLowerInvariant().Trim();

    return CultureInfo.CreateSpecificCulture(language);

  }

  catch (ArgumentException)

  {

    return null;

  }

}

Resolve the country

The next method uses the ResolveCulture() method above to create a RegionInfo object. The RegionInfo contains all the country information needed such as ISO code, EnglishName, NativeName and DisplayName. 

public static RegionInfo ResolveCountry()

{

  CultureInfo culture = ResolveCulture();

  if (culture != null)

    return new RegionInfo(culture.LCID);

 

  return null;

} 

Now I am able to get all the culture and country/region information I need based on the browser’s language, with a margin of inaccuracy I can live with.

Usage:

        RegionInfo ri = ResolveCountry();
        Response.Write("Display Name:" + ri.DisplayName );
        Response.Write("Native Name:" + ri.NativeName );