我有一个表单，在该表单中，我会根据父自定义帖子类型的ID在复选框列表中列出相关的自定义帖子类型，如图所示。

因此，当我选中4个选项的一个选项时，我想在下拉列表中列出我选中的自定义帖子的术语列表。

表单是用elementor pro构建的，但为了有帖子列表和分类术语，我使用代码（我使用我的函数，并将其包含在functions.php上的shortcode中）。

/*
 * Display list of  relationship field
 *
*/

function list_formation_caces(){
echo "<div class=\'golistgo\'>";
$args = array(
    \'post_type\' => \'categories\',
    \'posts_per_page\' => 20,
);
$loop = new WP_Query( $args );
while ( $loop->have_posts() ) : $loop->the_post();
    $formations = get_posts(array(
        \'post_type\' => \'formations\',
        \'post__in\' => array(16061),
        \'meta_query\' => array(
            array(
                \'key\' => \'categories\', // name of custom field
                \'value\' => \'"\' . get_the_ID() . \'"\', // matches exactly "123", not just 123. This prevents a match for "1234"
                \'compare\' => \'LIKE\'
            )
        )
    ));
    if($formations){
        foreach ($formations as $categorie){
            $image = get_field(\'image_form\');
            if($image){
                // Image variables.
                $url = $image[\'url\'];
                $title = $image[\'title\'];
                $alt = $image[\'alt\'];
                $caption = $image[\'caption\'];

                // Thumbnail size attributes.
                $size = \'thumbnail\';
                $thumb = $image[\'sizes\'][ $size ];
                $width = $image[\'sizes\'][ $size . \'-width\' ];
                $height = $image[\'sizes\'][ $size . \'-height\' ];
            }
            echo "<input type=\\"checkbox\\" class=\\"btn-check\\" name=\\"Description\\" value =\\"". get_the_title() .
                "\\" id=\\"". get_the_ID()  ."\\">";
            echo "<label class=\\"options-form\\" for=\'". get_the_ID() ."\'>";
                               echo "<div class=\\"image-cat\\">";
                                    echo get_the_post_thumbnail();
                               echo"</div>";
                               echo "<div class=\\"body-cat\\">";
                                    echo "<div  class=\\"title-formation\\">" ;
                                    echo "</div>";
                                    echo "<div  class=\\"title-cat\\">" ;
                                    echo the_title() . ":" . " <span  class=\\"describe-cat\\">" . get_field(\'type_machine\') . "</span>";
                                    echo "</div>";
                               echo "</div>";
            echo "</label>";
        }
    }
endwhile;
wp_reset_postdata();
echo "</div>";
}

function shortcode_list_categ_caces(){
            return (list_formation_caces()) ;
}
add_shortcode(\'list_formation_caces\', \'shortcode_list_categ_caces\');

function shortcode_total_count_checked(){

return ("<div class=\'count-checkboxes-wrapper\'>" . "<h2 class=\'title-count\'>" . "Vous avez choisis" .
    "<span id=\'count-checked-checkboxes\'> " . "  0" ."</span> catégorie(s)."." </h2>" .
    "</div>");
}
add_shortcode(\'count_checked\', \'shortcode_total_count_checked\');

function list_sessions_caces()
{
    $terms = get_terms( array(
        \'taxonomy\' => \'sessions\',
        \'hide_empty\' => false,
    ) );
    echo\'<label for="form-field-centre" class="elementor-field-label">Où se déroulera la formation ?</label>\';
    echo \'<div class="elementor-field elementor-select-wrapper ">\';
    echo \'<select name="CENTRE"  id="form-field-field_centre" class="elementor-field-textual elementor-size-sm">\';
    echo \'<option value="">Choisir une session de formation </option> \';
    foreach ($terms as $term) {
        echo \'<option value="\' . $term->name . \'">\' . $term->name . \'</option>\';
    }
    echo \'</select>\';
    echo\'</div>\';
}
function shortcode_list_sessions(){
    return (list_sessions_caces()) ;
}
add_shortcode(\'list_sessions_caces\', \'shortcode_list_sessions\');