/// <summary>
        /// Gets, sets, or restores a value of a legacy configuration option.
        /// </summary>
        private static object GetSetRestore(LocalConfiguration config, string option, object value, IniAction action)
        {
            PDOMySQLLocalConfig  local    = (PDOMySQLLocalConfig)config.GetLibraryConfig(PDOMySQLLibraryDescriptor.Singleton);
            PDOMySQLLocalConfig  @default = DefaultLocal;
            PDOMySQLGlobalConfig global   = Global;

            //switch (option)
            //{
            //    // local:

            //    // global:

            //}

            Debug.Fail("Option '" + option + "' is supported but not implemented.");
            return(null);
        }
        /// <summary>
        /// Writes PDO legacy options and their values to XML text stream.
        /// Skips options whose values are the same as default values of Phalanger.
        /// </summary>
        /// <param name="writer">XML writer.</param>
        /// <param name="options">A hashtable containing PHP names and option values. Consumed options are removed from the table.</param>
        /// <param name="writePhpNames">Whether to add "phpName" attribute to option nodes.</param>
        public static void LegacyOptionsToXml(XmlTextWriter writer, Hashtable options, bool writePhpNames) // GENERICS:<string,string>
        {
            if (writer == null)
                throw new ArgumentNullException("writer");
            if (options == null)
                throw new ArgumentNullException("options");

            PDOMySQLLocalConfig local = new PDOMySQLLocalConfig();
            PDOMySQLGlobalConfig global = new PDOMySQLGlobalConfig();
            PhpIniXmlWriter ow = new PhpIniXmlWriter(writer, options, writePhpNames);

            ow.StartSection("pdo");

            // local:

            // global:

            ow.WriteEnd();
        }
        /// <summary>
        /// Writes PDO legacy options and their values to XML text stream.
        /// Skips options whose values are the same as default values of Phalanger.
        /// </summary>
        /// <param name="writer">XML writer.</param>
        /// <param name="options">A hashtable containing PHP names and option values. Consumed options are removed from the table.</param>
        /// <param name="writePhpNames">Whether to add "phpName" attribute to option nodes.</param>
        public static void LegacyOptionsToXml(XmlTextWriter writer, Hashtable options, bool writePhpNames) // GENERICS:<string,string>
        {
            if (writer == null)
            {
                throw new ArgumentNullException("writer");
            }
            if (options == null)
            {
                throw new ArgumentNullException("options");
            }

            PDOMySQLLocalConfig  local  = new PDOMySQLLocalConfig();
            PDOMySQLGlobalConfig global = new PDOMySQLGlobalConfig();
            PhpIniXmlWriter      ow     = new PhpIniXmlWriter(writer, options, writePhpNames);

            ow.StartSection("pdo");

            // local:

            // global:

            ow.WriteEnd();
        }