我想实现一个插件，它在管理区域中获取2个字段，并将这些字段保存在选项中作为数组
我阅读了页面Custom Settings Page 但它似乎没有描述如何在选项中保存字段值，我们该如何做？

非常感谢。

<?php

/**
 * Class for registering persian font settings page under Settings.
 */
class PersianFont_Options_Page {

    public $page_title;
    public $menu_title;
    public $plugin_slug;
    public $plugin_hook;

    /**
     * Constructor.
     */
    function __construct() {

        $this->plugin_slug = \'persianfont\';
        $this->page_title = __(\'تنظیمات افزونه فارسی ساز قالب\', \'persianfont\');
        $this->menu_title = __(\'فارسی ساز قالب\', \'persianfont\');

        add_action( \'admin_menu\', [ $this, \'add_admin_menu\' ] );

        // Here you can check if plugin is configured (e.g. check if some option is set). If not, add new hook.
        // In this example hook is always added.
        add_action( \'admin_notices\', [ $this, \'add_admin_notices\' ] );

        add_action( \'admin_init\',  [ $this, \'register_settings\' ] );
    }

    /**
    * Registers a new settings page under Settings.
    */
    function add_admin_menu() {
        $this->plugin_hook = 
            add_options_page(
                $this->page_title,
                $this->menu_title,
                \'manage_options\', // capability
                $this->plugin_slug,
                [ $this, \'settings_page_content\' ] //output the content for this page
        );

        //var_dump($this->plugin_hook); // -> string(26) "settings_page_persian_font"
        if($this->plugin_hook){
            add_action( \'load-\' . $this->plugin_hook, [ $this, \'on_plugin_page_load\' ] );
        }

    }

    function on_plugin_page_load(){
        remove_action( \'admin_notices\', [ $this, \'add_admin_notices\' ] );
        $this->add_setting_page_help();
    }

    function add_admin_notices() {
        ?>
        <div id="notice" class="update-nag">
            <?php _e(\'افزونه فارسی ساز قالب پیکربندی نشده است. \', \'persianfont\'); ?>
            <a href="<?php menu_page_url( $this->plugin_slug, true ); ?>"><?php _e(\'لطفا هم اکنون پیکربندی نمائید.\', \'persianfont\'); ?></a>
        </div>
        <?php
    }

    function add_setting_page_help(){
        // We are in the correct screen because we are taking advantage of the load-* action (below)
        $help_content = 
            \'<p>\' . __( \'از این صفحه برای تنظیمات افزونه فارسی ساز قالب استفاده نمائید.\', \'persianfont\' ) . \'</p>\' .
            \'\';

        $screen = get_current_screen();
        //$screen->remove_help_tabs();
        $screen->add_help_tab(
        [
            \'id\'            => \'persianfont-default\',
            \'title\'         => __( \'Help\' ),
            \'content\'   => $help_content,
        ]);
        //add more help tabs as needed with unique id\'s

        // Help sidebars are optional
        $screen->set_help_sidebar(
            \'<p><strong>\' . __( \'For more information:\' ) . \'</strong></p>\' .
            \'<p><a href="https://parsmizban.com" target="_blank">\' . _( \'بازدید از پارس میزبان\' ) . \'</a></p>\'
        );
    }

    function register_settings() { // whitelist options
        register_setting(
            $this->plugin_slug, // option_group
            $this->plugin_slug, // option_name, for name property of tags
            [$this, \'process_inputs\'] // sanitize_callback
        );
            add_settings_section(
                \'load-font-setting\', // id attribute of tags
                __(\'تنظیمات مربوط به بارگذاری فونت ها\', \'persianfont\'), // title heading for the section
                function($args){ ?>
                    <p id="<?php echo esc_attr( $args[\'id\'] ); ?>"><?php _e(\'با استفاده از تنظیمات زیر، تعیین نمائید که فونت ها برای کدام بخش های سایت بارگذاری شوند.\', \'persianfont\'); ?></p>
                <?php
                }, // callback function to display content at the top of the section
                $this->plugin_slug // plugin slug, created by add_options_page()
            );
                add_settings_field(
                    \'frontend-font\', // id attribute of tag
                    __(\'بارگذاری فونت برای بخش اصلی سایت\', \'persianfont\'), // Title as lable for field
                    function(){
                        var_dump(get_option( \'persianfont\' ));
                        //$check_frontend_font = is_null(get_option( \'persianfont\' )[\'frontend-font\']) ? \'true\' : get_option( \'persianfont\' )[\'frontend-font\'];
                        ?>
                        <input type="checkbox" name="frontend-font" id="frontend-font" value="true" <?php //checked( \'true\', $check_frontend_font ); ?> />
                        <?php
                    }, // Callback function to echo input tag
                    $this->plugin_slug, // plugin slug, created by add_options_page()
                    \'load-font-setting\', // slug-name of the section
                    [
                        \'label_for\' => \'frontend-font\', // label for => tag id
                        \'class\'     => \'frontend-font\', // class for <tr>
                    ]
                );
                add_settings_field(
                    \'backend-font\', // id attribute of tag
                    __(\'بارگذاری فونت برای بخش مدیریت\', \'persianfont\'), // Title as lable for field
                    function(){
                        //$check_backend_font = is_null(get_option( \'persianfont\' )[\'backend-font\']) ? \'true\' : get_option( \'persianfont\' )[\'backend-font\'];
                        ?>
                        <input type="checkbox" name="backend-font" id="backend-font" value="true" <?php //checked( \'true\', $check_backend_font ); ?> />
                    <?php
                    }, // Callback function to echo input tag
                    $this->plugin_slug, // plugin slug, created by add_options_page()
                    \'load-font-setting\', // slug-name of the section
                    [
                        \'label_for\' => \'backend-font\', // label for => tag id
                        \'class\'     => \'backend-font\',  // class for <tr>
                    ]
                );

    }

    /**
     * Sanitize each setting field as needed
     *
     * @param array $input Contains all settings fields as array keys
     */
    public function process_inputs( $input ){
        // sanitize functions:
        // sanitize_email(), sanitize_file_name(), sanitize_html_class(), sanitize_key(), sanitize_meta(), sanitize_mime_type(),
        // sanitize_option(), sanitize_sql_orderby(), sanitize_text_field(), sanitize_textarea_field(), sanitize_title(),
        // sanitize_title_for_query(), sanitize_title_with_dashes(), sanitize_user()
        $options = [];
        if( isset( $input[\'frontend-font\'] ) and $input[\'frontend-font\'] == true ) {
            $options[\'frontend-font\'] = true;
        }else{
            $options[\'frontend-font\'] = false;
        }
        if( isset( $input[\'backend-font\'] ) and $input[\'backend-font\'] == true ){
            $options[\'backend-font\'] = true;
        }else{
            $options[\'backend-font\'] = false;
        }
        //update_option(\'persianfont\', $options);

        // add error/update messages
        // check if the user have submitted the settings
        // wordpress will add the "settings-updated" $_GET parameter to the url
/*      if ( isset( $_GET[\'settings-updated\'] ) ) {
            // add settings saved message with the class of "updated"
            add_settings_error(
                \'persianfont_messages\', // Slug title of setting
                \'wporg_message\', // Slug-name , Used as part of \'id\' attribute in HTML output.
                __( \'تنظیمات مورد نظر ذخیره شد.\', \'persianfont\' ), // message text, will be shown inside styled <div> and <p> tags
                \'updated\' // Message type, controls HTML class. Accepts \'error\' or \'updated\'.
            );
        }*/
        return $input;
    }

    /**
     * Settings page display callback.
     */
    function settings_page_content() {
        // check user capabilities
        if ( ! current_user_can( \'manage_options\' ) ) { return; }

        // var_dump( wp_load_alloptions() ); // print all options

        // show error/update messages
        settings_errors( \'persianfont_messages\' );
        ?>
        <div class="wrap">
            <h1 class="wp-heading-inline"><?php echo esc_html($this->page_title); ?></h1>
            <form method="post" action="options.php">
            <?php
                submit_button();
                settings_fields( $this->plugin_slug ); // This prints out all hidden setting fields
                do_settings_sections( $this->plugin_slug );
                submit_button();
            ?>
            </form>
        </div>
        <?php
    }

} // class

new PersianFont_Options_Page;