toLanguageTag method Null safety

String toLanguageTag()

Returns a syntactically valid Unicode BCP47 Locale Identifier.

Some examples of such identifiers: "en", "es-419", "hi-Deva-IN" and "zh-Hans-CN". See http://www.unicode.org/reports/tr35/ for technical details.

Implementation

String toLanguageTag() => _rawToString('-');