下面是一个“案例”（在自定义帖子类型中），用于拉取所有类别并将其显示为下拉菜单。我怎样才能做同样的事情，但把它变成一个复选框列表？

    //tax_select - this lists all of the categories in a drop-down, we want to change to a checkbox
case \'tax_select\':
echo \'<select name="\'.$field[\'id\'].\'" id="\'.$field[\'id\'].\'">
        //<option value="">Select One</option>\'; // Select One
$terms = get_terms($field[\'id\'], \'get=all\');
$selected = wp_get_object_terms($post->ID, $field[\'id\']);
foreach ($terms as $term) {
    if (!empty($selected) && !strcmp($term->slug, $selected[0]->slug))
        echo \'<option value="\'.$term->slug.\'" selected="selected">\'.$term->name.\'</option>\';
    else
        echo \'<option value="\'.$term->slug.\'">\'.$term->name.\'</option>\';
}
$taxonomy = get_taxonomy($field[\'id\']);
echo \'</select><br /><span class="description"><a href="\'.get_bloginfo(\'home\').\'/wp-admin/edit-tags.php?taxonomy=\'.$field[\'id\'].\'">Manage \'.$taxonomy->label.\'</a></span>\';
break;

    // Save the Data
function save_custom_meta($post_id) {
global $custom_meta_fields;

// verify nonce
if (!wp_verify_nonce($_POST[\'custom_meta_box_nonce\'], basename(__FILE__)))
    return $post_id;
// check autosave
if (defined(\'DOING_AUTOSAVE\') && DOING_AUTOSAVE)
    return $post_id;
// check permissions
if (\'page\' == $_POST[\'post_type\']) {
    if (!current_user_can(\'edit_page\', $post_id))
        return $post_id;
    } elseif (!current_user_can(\'edit_post\', $post_id)) {
        return $post_id;
}

// loop through fields and save the data
foreach ($custom_meta_fields as $field) {
            if($field[\'type\'] == \'tax_select\') continue;
    $old = get_post_meta($post_id, $field[\'id\'], true);
    $new = $_POST[$field[\'id\']];
    if ($new && $new != $old) {
        update_post_meta($post_id, $field[\'id\'], $new);
    } elseif (\'\' == $new && $old) {
        delete_post_meta($post_id, $field[\'id\'], $old);
    }
} // end foreach

    // save taxonomies
$post = get_post($post_id);
$category = $_POST[\'category\'];
wp_set_object_terms( $post_id, $category, \'category\' );
}
add_action(\'save_post\', \'save_custom_meta\');