WooCommerce - как редактировать и настраивать поля в порядке админки

Question

В Wordpress 5.3.2 и с WooCommerce 4.0.1 я пытаюсь добавить новые поля в область выставления счетов и редактировать и сохранять их в порядке admin.

Я пробовал код, доступный на https://docs.woocommerce.com/document/tutorial-customising-checkout-fields-using-actions-and-filters/ - добавление специального специального поля, но редактирование и сохранение пользовательского поля не помогло.

Я искал в Интернете и нашел следующее решение, позволяющее мне редактировать поля: но я все еще не могу сохранить их в порядке области администратора:

// Add fiels in checkout
add_filter( 'woocommerce_checkout_fields' , 'adauga_campuri_companie' );
function adauga_campuri_companie( $fields ) {
$fields['billing']['checkbox_pj'] = array(
        'type'      => 'checkbox',
        'label'     => __('Factura pe persoana juridica', 'woocommerce'),
        'class'     => array('form-row-wide'),
        'clear'     => true
     );

     $fields['billing']['billing_ncompanie'] = array(
        'label'     => __('Nume companie', 'woocommerce'),
    'placeholder'   => _x('Nume companie', 'placeholder', 'woocommerce'),
    'required'  => false,
    'class'     => array('form-row-wide'),
    'clear'     => true
     );

     $fields['billing']['billing_jcompanie'] = array(
        'label'     => __('Nr. inregistare Registrul Comertului', 'woocommerce'),
    'placeholder'   => _x('Nr. inregistare Registrul Comertului', 'placeholder', 'woocommerce'),
    'required'  => false,
    'class'     => array('form-row-wide'),
    'clear'     => true
     );


    $fields['billing']['billing_cuicompanie'] = array(
        'label'     => __('Cod Unic Inregistrare', 'woocommerce'),
    'placeholder'   => _x('Cod Unic Inregistrare', 'placeholder', 'woocommerce'),
    'required'  => false,
    'class'     => array('form-row-wide'),
    'clear'     => true
     );


    $fields['billing']['billing_banca'] = array(
        'label'     => __('Banca', 'woocommerce'),
    'placeholder'   => _x('Banca', 'placeholder', 'woocommerce'),
    'required'  => false,
    'class'     => array('form-row-wide'),
    'clear'     => true
     );


     $fields['billing']['billing_cont'] = array(
        'label'     => __('Cont Bancar', 'woocommerce'),
    'placeholder'   => _x('Cont bancar', 'placeholder', 'woocommerce'),
    'required'  => false,
    'class'     => array('form-row-wide'),
    'clear'     => true
     );
      return $fields;
}

//Show the fields only when the checkbox is checked


add_action( 'woocommerce_after_checkout_form', 'afisare_conditionata_date_companie', 6);

function afisare_conditionata_date_companie() {

  ?>
    <script type="text/javascript">
            function uncheck() {

                jQuery('#billing_ncompanie_field').hide();
                jQuery('#billing_jcompanie_field').hide();
                jQuery('#billing_cuicompanie_field').hide();
                jQuery('#billing_banca_field').hide();
                jQuery('#billing_cont_field').hide();
            }
            function check() {

                jQuery('#billing_ncompanie_field').show();  
               jQuery('#billing_jcompanie_field').show();  
               jQuery('#billing_cuicompanie_field').show();  
               jQuery('#billing_banca_field').show();  
               jQuery('#billing_cont_field').show(); 
            }
            console.log('before condition');
            if (jQuery('#checkbox_pj:checked').length == 0) {
                uncheck();
            } else {
               check();
            }
            jQuery('input#checkbox_pj').change(function(){

            if (this.checked) {
                check();
            } else {
                uncheck();
            }
        });

    </script>
  <?php

}


/**
 * Validate the fields at checkout
 */
add_action('woocommerce_checkout_process', 'validare_campuri_companie');

function validare_campuri_companie() {
    if (isset( $_POST['checkbox_pj'] ))
    {
        if ( ! $_POST['billing_ncompanie'] )
            wc_add_notice( __( 'Va rugam sa introduceti numele companiei.' ), 'error' );
        if ( ! $_POST['billing_jcompanie'] )
            wc_add_notice( __( 'Va rugam sa introduceti Nr. inregistare la Registrul Comertului.' ), 'error' );
        if ( ! $_POST['billing_cuicompanie'] )
            wc_add_notice( __( 'Va rugam sa introduceti Codul Unic de Inregistrare.' ), 'error' );
        if ( ! $_POST['billing_banca'] )
            wc_add_notice( __( 'Va rugam sa introduceti banca.' ), 'error' );
        if ( ! $_POST['billing_cont'] )
            wc_add_notice( __( 'Va rugam sa introduceti contul bancar.' ), 'error' );
    }
}

/**
 * Update the order meta with field value
 */
add_action( 'woocommerce_checkout_update_order_meta', 'date_companie_update_order_meta' );
// Save the custom editable field value as order meta data and update order item meta data


function date_companie_update_order_meta( $order_id ) {
    if (isset( $_POST['checkbox_pj'] )) 
    {
        if ( ! empty( $_POST['billing_ncompanie'] ) ) {
            update_post_meta( $order_id, 'Nume companie', sanitize_text_field( $_POST['billing_ncompanie'] ) );
        }
        if ( ! empty( $_POST['billing_jcompanie'] ) ) {
            update_post_meta( $order_id, 'Nr. inregistare Registrul Comertului', sanitize_text_field( $_POST['billing_jcompanie'] ) );
        }
        if ( ! empty( $_POST['billing_cuicompanie'] ) ) {
            update_post_meta( $order_id, 'Cod Unic Inregistrare', sanitize_text_field( $_POST['billing_cuicompanie'] ) );
        }
        if ( ! empty( $_POST['billing_banca'] ) ) {
            update_post_meta( $order_id, 'Banca', sanitize_text_field( $_POST['billing_banca'] ) );
        }
        if ( ! empty( $_POST['billing_cont'] ) ) {
            update_post_meta( $order_id, 'Cont Bancar', sanitize_text_field( $_POST['billing_cont'] ) );
        }
    }
}

// Add the fields to the emails

add_filter('woocommerce_email_order_meta_keys', 'campuri_companie_order_meta_keys');

function campuri_companie_order_meta_keys( $keys ) {
     $keys[] = 'Nume companie' ;
     $keys[] = 'Nr. inregistare Registrul Comertului';
     $keys[] = 'Cod Unic Inregistrare';
     $keys[] = 'Banca' ; 
     $keys[] = 'Cont Bancar' ; 
     return $keys;
}



//Add the fiels to thank you page and view order
add_action( 'woocommerce_thankyou', 'detalii_companie_comanda_thanyou_page', 20 );
add_action( 'woocommerce_view_order', 'detalii_companie_comanda_thanyou_page', 20 );

function detalii_companie_comanda_thanyou_page( $order_id ){ 
    $meta = get_post_meta( $order_id, 'checkbox_pj', true );
    if (isset($meta)  && !empty(get_post_meta( $order_id, 'Nume companie', true ))) {
?>
    <h2>Date facturare companie</h2>
    <p>
         Nume companie: <?php echo get_post_meta( $order_id, 'Nume companie', true ); ?>
    <br/>
         Nr. inregistare Registrul Comertului: <?php echo get_post_meta( $order_id, 'Nr. inregistare Registrul Comertului', true ); ?>
    <br/>
         Cod Unic Inregistrare: <?php echo get_post_meta( $order_id, 'Cod Unic Inregistrare', true ); ?>
    <br/>
         Banca: <?php echo get_post_meta( $order_id, 'Banca', true ); ?>
    <br/>
         Cont bancar: <?php echo get_post_meta( $order_id, 'Cont Bancar', true ); ?>
    </p>
<?php 
    }                                                                                                               
}


// Backend: Display editable custom billing fields in admin
add_filter( 'woocommerce_admin_billing_fields' , 'order_admin_custom_fields' );
function order_admin_custom_fields( $fields ) {
   global $theorder;

   $fields['checkbox_pj'] = array(
        'type'      => 'checkbox',
        'label'     => __('Factura pe persoana juridica', 'woocommerce'),
        'value'     => get_post_meta( $theorder->id, 'checkbox_pj', true ),
        'class'     => array('form-field-wide'),
        'clear'     => true
     );

    $fields['ncompanie'] = array(
        'label' => __( 'Nume companie', 'woocommerce' ),
        'value'     => get_post_meta( $theorder->id, 'Nume companie', true),
        'show'  => true,
        'wrapper_class' => 'form-field-wide',
        'style' => '',
    );


    $fields['jcompanie'] = array(
        'label' => __( 'Nr. inregistare Registrul Comertului', 'woocommerce' ),
        'value'     => get_post_meta( $theorder->id, 'Nr. inregistare Registrul Comertului', true),
        'show'  => true,
        'wrapper_class' => 'form-field-wide',
        'style' => '',
    );


    $fields['cuicompanie'] = array(
        'label' => __( 'Cod Unic Inregistrare', 'woocommerce' ),
        'value'     => get_post_meta( $theorder->id, 'Cod Unic Inregistrare', true),
        'show'  => true,
        'wrapper_class' => 'form-field-wide',
        'style' => '',
    );

    $fields['banca'] = array(
        'label' => __( 'Banca', 'woocommerce' ),
        'value'     => get_post_meta( $theorder->id, 'Banca', true),
        'show'  => true,
        'wrapper_class' => 'form-field-wide',
        'style' => '',
    );

    $fields['cont'] = array(
        'label' => __( 'Cont Bancar', 'woocommerce' ),
        'value'     => get_post_meta($theorder->id, 'Cont Bancar', true),
        'show'  => true,
        'wrapper_class' => 'form-field-wide',
        'style' => '',
    );
    return $fields;
}

//Save the fields

add_action( 'woocommerce_process_shop_order_meta', 'save_custom_code_after_order_details', 12, 2 );

function save_custom_code_after_order_details( $post_id, $post ) {
    if(isset( $_POST['checkbox_pj'] )) 
    {
        if ( ! empty( $_POST['billing_ncompanie'] ) ) {
            update_post_meta( $post_id, '_billing_ncompanie', sanitize_text_field( $_POST['billing_ncompanie'] ) );
        }
        if ( ! empty( $_POST['billing_jcompanie'] ) ) {
            update_post_meta( $post_id, '_billing_jcompanie', sanitize_text_field( $_POST['billing_jcompanie'] ) );
        }
        if ( ! empty( $_POST['billing_cuicompanie'] ) ) {
            update_post_meta( $post_id, '_billing_cuicompanie', sanitize_text_field( $_POST['billing_cuicompanie'] ) );
        }
        if ( ! empty( $_POST['billing_banca'] ) ) {
            update_post_meta( $post_id, '_billing_banca', sanitize_text_field( $_POST['billing_banca'] ) );
        }
        if ( ! empty( $_POST['billing_cont'] ) ) {
            update_post_meta( $post_id, '_billing_cont', sanitize_text_field( $_POST['billing_cont'] ) );
        }
}
}

Я был бы очень признателен за любую помощь в создании кода (для редактирования и сохранения пользовательских полей в области администратора).

Спасибо!