按姓氏而非姓名对分类进行排序

Question

我创建了一个作者分类法。每个作者在姓名字段中都有姓名。稍后在分类页面上，列表按字母顺序显示。

<?php
          $taxonomy = 'autorzy'; // <== Here define your custom taxonomy
            $sorted   = array(); // Initializing

            // Get all terms alphabetically sorted
            $terms = get_terms( array(
                'taxonomy'   => $taxonomy,
                'hide_empty' => false,
                'orderby'    => 'name'
            ) );

            // Loop through the array of WP_Term Objects
            foreach( $terms as $term ) {
                $term_name    = $term->name;
                $image = get_field('obrazek_wyrozniajacy', $term);
                $term_link    = get_term_link( $term, $taxonomy );
                $first_letter = strtoupper($term_name[0]);
                
                // Group terms by their first starting letter
                if( ! empty($term_link) ) {
                    $sorted[$first_letter][] = '<li><a href="'.$term_link.'">' .'<img src="'.$image['url'].'" />'.$term_name.'</a></li>';
                } else {
                    $sorted[$first_letter][] = '<li>'.$term_name.'</li>';
                }
            }

            // Loop through grouped terms by letter to display them by letter
            foreach( $sorted as $letter => $values ) {
                echo '<div class="tax-by-letter" id="tax-letter-'.$letter.'">
                <h3 class="tax-letter-'.$letter.'">'.$letter.'</h3>
                <ul class="nav">' . implode('', $values) . '</ul>
                </div>';
            }


          ?>

问题是作者按名字排序，我希望按姓氏排序。我需要改进什么？

Answer 1

您无法轻松地以有效的方式对部分字符串进行排序，因此我建议在保存帖子时将

firstName

和

lastName

分开，并将它们分别存储在自己的元数据字段中：

// Breaks the fullname into first and last on-save and adds as metadata
add_action( 'created_autorzy', 'save_autorzy_meta', 10, 2 );

function save_autorzy_meta( $term_id, $tt_id ){
    $taxonomy = 'autorzy';
    $term = get_term($term_id, $taxonomy);

    if ( isset($term['name']) ){
        $name = explode(" ", $term['name']);
        $firstName = $name[0] ?? "";
        $lastName = $name[1] ?? "";

        update_term_meta( $term_id, 'firstName', $firstName );
        update_term_meta( $term_id, 'lastName', $lastName );
    }
}

// Add a query for our taxonomy with a custom metaquery
$result = new WP_Query( array(
    'tax_query' => array(
        array(
            'taxonomy' => $taxonomy,
            'hide_empty' => false,
        ),
    ),
    'meta_query' => array(
        'relation' => 'AND',
        'last_names' => array(
            'key' => 'lastName',
            'compare' => 'EXISTS',
        ),
        'first_names' => array(
            'key' => 'firstName',
            'compare' => 'EXISTS',
        ), 
    ),
    'orderby' => 'meta_value_num',
    'meta_key' => 'lastName',
    'order' => 'ASC',
) );

文档：

created_{$taxonomy}

- https://developer.wordpress.org/reference/hooks/created_taxonomy/

update_term_meta()

- https://developer.wordpress.org/reference/functions/update_term_meta/

taxonomy query params

- https://developer.wordpress.org/reference/classes/wp_query/#taxonomy-parameters

orderby with meta_value_num

- https://developer.wordpress.org/reference/classes/wp_query/#custom-field-post-meta-parameters