diff --git a/app_language.cpp b/app_language.cpp
index 6971967..d8d794f 100644
--- a/app_language.cpp
+++ b/app_language.cpp
@@ -686,9 +686,11 @@ public:
 				notify_.erase(it);
 		}
 	}
-	int get_default_string_id(const char* str)
+	int get_string_id(const char* str, bool def)
 	{
-		for (auto& v : map_default_)
+		std::map<uint32_t, std::string>* lang = def ? &map_default_ : pak_now_;
+
+		for (auto& v : *lang)
 		{
 			if (v.second == str)
 				return v.first;
@@ -696,6 +698,42 @@ public:
 
 		return -1;
 	}
+	const char* transform_language(const char* in, bool to_def, bool* found)
+	{
+		if (cur_cp_ == DEFAULT_CODE_PAGE)
+		{
+			if (found)
+				*found = true;
+
+			return in;
+		}
+
+		int id = get_string_id(in, false);
+		std::map<uint32_t, std::string>* t = to_def ? &map_default_ : pak_now_;
+
+		if (id == -1)
+		{
+			if (found)
+				*found = false;
+
+			return in;
+		}
+
+		if (t->count(id))
+		{
+			if (found)
+				*found = true;
+
+			return (*t)[id].c_str();
+		}
+		else
+		{
+			if (found)
+				*found = false;
+
+			return in;
+		}
+	}
 };
 lang_mgr* lang_mgr::inst_ = nullptr;
 
@@ -729,8 +767,17 @@ extern "C"
 		lang_mgr::instance()->register_language_changed_notify(lan_changed, reg, param);
 	}
 
-	int lang_get_string_id(const char* utf8_hz)
+	int lang_get_string_id(const char* str, bool def_lang)
 	{
-		return lang_mgr::instance()->get_default_string_id(utf8_hz);
+		return lang_mgr::instance()->get_string_id(str, def_lang);
+	}
+
+	const char* to_default_language(const char* str, bool* ok)
+	{
+		return lang_mgr::instance()->transform_language(str, true, ok);
+	}
+	const char* from_default_language(const char* str, bool* ok)
+	{
+		return lang_mgr::instance()->transform_language(str, false, ok);
 	}
 }