Unity3D Internationalization (I18N)

English.js

#pragma strict

public class English {
  public static var lang : Hashtable = {
    // General
    "game_name": "My Awesome Game"

    // Menus
    , "new_game"                  : "New Game"
    , "save_game"                 : "Save Game"
    , "load_game"                 : "Load Game"
    , "quit_game"                 : "Quit Game"
    , "end_game"                  : "End Game"
    , "settings"                  : "Settings"

  };
}

ExampleUsage.js

#pragma strict

function Start() {
  Debug.Log(I18N.Get('game_name'));
}

German.js

#pragma strict

public class German {
  public static var lang : Hashtable = {
    // General
    "game_name": "Mein ehrfürchtiges Spiel"

    // Menus
    , "new_game"                  : "Neues Spiel"
    , "save_game"                 : "Spiel speichern"
    , "load_game"                 : "Spiel laden"
    , "quit_game"                 : "Spiel verlassen"
    , "end_game"                  : "Spiel beenden"
    , "settings"                  : "Einstellungen"

  };
}

I18N.js

#pragma strict

public class I18N {
  private static var defaultLang   : String = "en";
  private static var gameLang      : String = "";

  private static var noTranslationText : String = "Translation missing for {0}";
  private static  var langs : Hashtable = {
    "en": English.lang,
    "de": German.lang
  };

  private static function CheckAndSetUserLanguage() : boolean {
    switch(Application.systemLanguage) {
        case SystemLanguage.Afrikaans: SetLang("af"); break;
        case SystemLanguage.Arabic: SetLang("ar"); break;
        case SystemLanguage.Basque: SetLang("eu"); break;
        case SystemLanguage.Belarusian: SetLang("be"); break;
        case SystemLanguage.Bulgarian: SetLang("bg"); break;
        case SystemLanguage.Catalan: SetLang("ca"); break;
        case SystemLanguage.Chinese: SetLang("zh"); break;
        case SystemLanguage.Czech: SetLang("cs"); break;
        case SystemLanguage.Danish: SetLang("da"); break;
        case SystemLanguage.Dutch: SetLang("nl"); break;
        case SystemLanguage.English: SetLang("en"); break;
        case SystemLanguage.Estonian: SetLang("et"); break;
        case SystemLanguage.Faroese: SetLang("fo"); break;
        case SystemLanguage.Finnish: SetLang("fu"); break;
        case SystemLanguage.French: SetLang("fr"); break;
        case SystemLanguage.German: SetLang("de"); break;
        case SystemLanguage.Greek: SetLang("el"); break;
        case SystemLanguage.Hebrew: SetLang("he"); break;
        case SystemLanguage.Icelandic: SetLang("is"); break;
        case SystemLanguage.Indonesian: SetLang("id"); break;
        case SystemLanguage.Italian: SetLang("it"); break;
        case SystemLanguage.Japanese: SetLang("ja"); break;
        case SystemLanguage.Korean: SetLang("ko"); break;
        case SystemLanguage.Latvian: SetLang("lv"); break;
        case SystemLanguage.Lithuanian: SetLang("lt"); break;
        case SystemLanguage.Norwegian: SetLang("nn"); break; // TODO: Check
        case SystemLanguage.Polish: SetLang("pl"); break;
        case SystemLanguage.Portuguese: SetLang("pt"); break;
        case SystemLanguage.Romanian: SetLang("ro"); break;
        case SystemLanguage.Russian: SetLang("ru"); break;
        case SystemLanguage.SerboCroatian: SetLang("sr"); break; // TODO: Check
        case SystemLanguage.Slovak: SetLang("sk"); break;
        case SystemLanguage.Slovenian: SetLang("sl"); break;
        case SystemLanguage.Spanish: SetLang("es"); break;
        case SystemLanguage.Swedish: SetLang("sv"); break;
        case SystemLanguage.Thai: SetLang("th"); break;
        case SystemLanguage.Turkish: SetLang("tr"); break;
        case SystemLanguage.Ukrainian: SetLang("uk"); break;
        case SystemLanguage.Vietnamese: SetLang("vi"); break;
        case SystemLanguage.ChineseSimplified: SetLang("zh_Hans"); break;
        case SystemLanguage.ChineseTraditional: SetLang("zh_Hant"); break;
        case SystemLanguage.Unknown: SetLang(defaultLang); break; // Unknow Fallback to defaultLang
        case SystemLanguage.Hungarian: SetLang("hu"); break;
    };

    if(gameLang.length > 0) {
      return true;
    }

    return false;
  }

  public static function GetCurrentLang() : String {
    CheckAndSetUserLanguage();

    return gameLang;
  }

  public static function SetLang(lang:String) : void {
    if(langs.ContainsKey(lang)) {
      gameLang = lang;
    } else {
      gameLang = defaultLang;
    }
  }

  /**
   * Example use: I18N.Get("game_name") -> "My Awesome Game"
   */
  public static function Get(key:String) : String {
    return Get(key, {});
  }

  public static function Get(key:String, args:Hashtable) : String {

    var lang : Hashtable = langs[GetCurrentLang()] as Hashtable;
    var value : String = lang[key] as String;


    if(value.length == 0) {
      return String.Format(noTranslationText, key);
    } else {
      return StringManipulation.Format(value, args);
    }
  }
}