下面是我的简单插件设置页面代码。它工作并保存一个选项（“EN”、“CZ”）。

但是，我要做的是在保存选项后运行一个函数（见最下面）。我使用wordpress函数：

do_action( "update_option_{$option}", mixed $old_value, mixed $value, string $option )

有趣的是，上周同样的代码也起了作用；现在，我在函数中尝试回显的任何内容都不会被打印出来，所以我假设函数甚至没有开始运行。

谁能给我指一下这里的正确方向吗？

<?php
add_action( \'admin_menu\', \'cmi_csv_import_plugin_page\' );

// tick
function cmi_csv_import_plugin_page() {
 
    add_options_page(
        \'CSV Import - PUDR\', // page <title>Title</title>
        \'CSV Import\', // menu link text
        \'manage_options\', // capability to access the page
        \'cmi-csv-import\', // page URL slug
        \'cmi_csv_page_content\', // callback function /w content
        5 // priority
    );
 
}

function cmi_csv_page_content () {
    ?>
    <div class="wrap">
        <h2>Import CSV</h2>
        <form action="options.php" method="post">
        <?php
        // this is what the setting is called and how you retrieve the option later! (with get_options)
        settings_fields( \'cmi_lang\' );
        // slug name of the page whose settings sections you want to output
        // Use this in a settings page callback function to output all the 
        // sections and fields that were added to that $page with add_settings_section() and add_settings_field()
        do_settings_sections( \'cmi-csv-import\' );
        submit_button( \'Aktualizovat metadata\', \'primary\' );
        ?>
        </form>
    </div>

<?php
}

// add an action on admin init
//
//
//
add_action (\'admin_init\', \'cmi_csv_admin_init\');

function cmi_csv_admin_init () {
    // a/ register settings
    $args = array(
        \'type\' => \'string\',
        // ↓ callable
        \'sanitize_callback\' => \'cmi_csv_validate_options\',
        \'default\' => NULL
        );
    register_setting (\'cmi_lang\', \'cmi_lang\', $args);

    // b/ add a settings section
    add_settings_section (
        \'cmi-csv-section-main\',
        \'Import CSV (metadata PUDR)\',
        // callable ↓ - echoes anything in the section
        \'cmi_csv_section_text\',
        // page name
        \'cmi-csv-import\'
    );

    // c/ add a settings field
    add_settings_field (
        \'cmi_lang\',
        \'Jazyk aktualizovaného pole\',
        // ↓ callback
        \'cmi_csv_setting_jazyk\',
        \'cmi-csv-import\',
        \'cmi-csv-section-main\'
    );
};

function cmi_csv_section_text() {

    echo \'<p>Nastavte jazyk.</p>\';

};

function cmi_csv_setting_jazyk () {
    // Get option \'beast_mode\' value from the database
    // Set to \'disabled\' as a default if the option does not exist
    $options = get_option( \'cmi_lang\', \'EN\');
    // Define the radio button options
    $items = array( \'EN\', \'CZ\');
    /*$jazyk = get_option (\'cmi_lang\');*/
    foreach( $items as $item ) {
        // Loop the two radio button options and select if set in the option value
        echo "<label><input " . checked( $item, $options, false) . " 
        value=\'" . esc_attr( $item ) . "\' name=\'cmi_lang\' 
        type=\'radio\'/> " . esc_html( $item ) . "</label><br/>";
    }
}

function cmi_csv_validate_options ($input) {
    $input = sanitize_text_field( $input );
    return $input;
};
  
add_action(\'update_option_cmi_lang\', function($old, $new) {

    if (!$new) {
        echo "didn\'t run";
        return;
    };

/// DO SOME STUFF 

}, 1, 2);