UnityEditor.LocalizationDatabase.GetAvailableEditorLanguages C# (CSharp) Method

        internal static extern SystemLanguage[] GetAvailableEditorLanguages();
        [MethodImpl(MethodImplOptions.InternalCall)]

        internal static SettingsProvider CreateLanguagesProvider()
        {
            var editorLanguages = LocalizationDatabase.GetAvailableEditorLanguages();

            if (m_EditorLanguageNames == null || m_EditorLanguageNames.Length != editorLanguages.Length)
            {
                m_EditorLanguageNames = new GUIContent[editorLanguages.Length];

                for (int i = 0; i < editorLanguages.Length; ++i)
                {
                    var culture  = LocalizationDatabase.GetCulture(editorLanguages[i]);
                    var langName = new System.Globalization.CultureInfo(culture).NativeName;

                    // Due to the issue 1088990, workaround for both Chinese is necessary.
                    // This workaround should be removed just after the fix.
                    if (editorLanguages[i] == SystemLanguage.ChineseSimplified)
                    {
                        byte[] letters = { 0xE7, 0xAE, 0x80, 0xE4, 0xBD, 0x93, 0xE4, 0xB8, 0xAD, 0xE6, 0x96, 0x87 };
                        langName = System.Text.Encoding.UTF8.GetString(letters);
                    }
                    else if (editorLanguages[i] == SystemLanguage.ChineseTraditional)
                    {
                        byte[] letters = { 0xE7, 0xB9, 0x81, 0xE9, 0xAB, 0x94, 0xE4, 0xB8, 0xAD, 0xE6, 0x96, 0x87 };
                        langName = System.Text.Encoding.UTF8.GetString(letters);
                    }

                    // not in stable languages list - display it as experimental language
                    if (ArrayUtility.FindIndex(m_stableLanguages, v => v == editorLanguages[i]) < 0)
                    {
                        m_EditorLanguageNames[i] = EditorGUIUtility.TextContent(string.Format("{0} (Experimental)", langName));
                    }
                    else
                    {
                        m_EditorLanguageNames[i] = EditorGUIUtility.TextContent(langName);
                    }
                }
                ArrayUtility.Insert(ref m_EditorLanguageNames, 0, EditorGUIUtility.TextContent(""));
                GUIContent defaultLanguage = EditorGUIUtility.TextContent(string.Format("Default ( {0} )", LocalizationDatabase.GetDefaultEditorLanguage().ToString()));
                ArrayUtility.Insert(ref m_EditorLanguageNames, 0, defaultLanguage);
            }

            if (editorLanguages.Length > 1)
            {
                var settings = new PreferencesProvider("Preferences/Languages");
                settings.guiHandler = searchContext => { OnGUI(searchContext, settings.ShowLanguage); };
                return(settings);
            }

            return(null);
        }