我有一个插件，其中有一个部分允许用户通过指定页面id来选择插件工作的页面。但我希望他能够从网站上可用的页面中选择页面。

这可以通过下拉列表或复选框来实现。

我的代码在插件的主文件中如下所示：

register_setting( \'rex_plug_options\', \'rex_plug_options\', \'rex_plug_settings_validate\' );
add_settings_field(\'rex_plugbox_text_exit_pop_selected_pages\', \'Select Pages (comma seprated page ID E.G.:  12,32,434)\', \'rex_plugbox_text_exit_pop_selected_pages\', \'rex_plug_box\', \'rex_plug_main_box\');
<?php
}
function rex_plugbox_text_exit_pop_selected_pages(){
global $rex_plug_options;
if(!isset($rex_plug_options["rex_plugbox_text_exit_pop_selected_pages"]))   {
    $rex_plug_options["rex_plugbox_text_exit_pop_selected_pages"] = "";
}
?>
    <textarea id="rex_plugbox_text_exit_pop_selected_pages" type="text" name="rex_plug_options[rex_plugbox_text_exit_pop_selected_pages]" ><?php echo sanitize_text_field( $rex_plug_options["rex_plugbox_text_exit_pop_selected_pages"] ); ?></textarea>

<?php
}

现在，这适用于文本区域，我希望它是一个下拉列表。我该怎么做？

我试过这样做：

 <select name="rex_plug_options[page_id]">
                        <?php
                        if( $pages = get_pages() ){
                            foreach( $pages as $page ){
                                echo \'<option value="\' . $page->ID . \'" \' . selected( $page->ID, $options[\'page_id\'] ) . \'>\' . $page->post_title . \'</option>\';
                            }
                        }
                        ?>
                    </select>

这将显示选择字段，但不确定如何使用此页面中选择的内容更新数据库选项数组字段。

register_setting( \'rex_plug_options\', \'rex_plug_options\', \'rex_plug_settings_validate\' );
add_settings_field(\'rex_plugbox_text_exit_pop_selected_pages\', \'Select Pages\', \'rex_plugbox_text_exit_pop_selected_pages\', \'rex_plug_box\', \'rex_plug_main_box\');
//with selectbox you cannot select multiple pages. If you need that try checkbox

function rex_plugbox_text_exit_pop_selected_pages(){
    global $rex_plug_options;
    if(!isset($rex_plug_options["rex_plugbox_text_exit_pop_selected_pages"]))   {
        $rex_plug_options["rex_plugbox_text_exit_pop_selected_pages"] = "";
    }
?>
    <select id="rex_plugbox_text_exit_pop_selected_pages" name="rex_plug_options[rex_plugbox_text_exit_pop_selected_pages]">
    <?php
    if( $pages = get_pages() ){
        foreach( $pages as $page ){
            echo \'<option value="\' . $page->ID . \'" \' . selected( $page->ID, $rex_plug_options["rex_plugbox_text_exit_pop_selected_pages"] ) . \'>\' . $page->post_title . \'</option>\';
        }
    }
    ?>
    </select>
<?php
}