Probably an unmanaged API like IsValidLanguageGroup , IsValidLocaleName (or IsValidLocale ) or IsValidCodePage is what you are looking for
For example, the code
if (IsValidLanguageGroup (LGRPID_ARABIC, LGRPID_INSTALLED) ||
IsValidLanguageGroup (LGRPID_TURKIC, LGRPID_INSTALLED) ||
IsValidLanguageGroup (LGRPID_HEBREW, LGRPID_INSTALLED)) {
// RTL is supported
}
(RTL), Windows. .NET API, , , CultureInfo.GetCultures .
. , , . .