SIDENOTE: This function can be used even if have posts belongs to one taxonomy only. You don’t need to have a post that belongs to two or more taxonomies within the same hierarchy. I have made this function very flexible
It is always a problem for me to display a category list or term list for a post if the following conditions occur
-
Having a post having terms that belongs to two different taxonomies
-
Using one template to display posts, and you have posts that have terms belonging to more that one taxonomy
You come to a situation where you need to duplicate functions, one for each taxonomy. For instance, a post belongs to terms in two taxonomies, mytax1 and mytax2. To display the term list, you have to do
echo get_the_term_list( $post->ID, 'mytax1' );
echo get_the_term_list( $post->ID, 'mytax2' );
This become a mess when the next post belongs to the default taxonomy category
I went and wrote a function that combines all in one, one function to display all terms of all taxonomies belonging to a post, and this function can be used to display any taxonomy of the build in taxonomies (except post_format)
Here is how the function works:
1.) This function makes use of get_the_term_list() to display the term list, so this function uses the same functionality as get_the_term_list()
2.) Must be used inside the loop. This function will not work outside the loop
3.) The post ID and taxonomy name are passed by default to the get_the_term_list() function
4.) Here is the list of the arguments
before (string)(optional) Leading text
Default: empty string
sep (string)(optional) String to separate tags
Default: empty string
after (string)(optional) Trailing text
Default: empty string
display_tax_name (bool)(optional) Should the taxonomy name be displayed in front of the list.
Default: false
taxonomy_sep (string)(optional) Text used to separate the taxonomy name from the term list
Default:
': 'multi_tax_sep (string)(optional) If the post have terms that belongs to more than one taxonomy, the text used to separate the two or more term lists
Default:
</br>hierarchical (bool)(optional) Should the list display hierarchical taxonomies (like categories ) or non-hierarchical taxonomies (like post tags)
Default: true
5.) The arguments can be passed as an array or as a string to the function
6.) Needs PHP 5.4+
This will work (string)
'display_tax_name=" . true ."&hierarchical=" . false . "&taxonomy_sep=' . html_entity_decode( '» ' )
And this will work
$args = [
'display_tax_name' => true,
'hierarchical' => false,
'taxonomy_sep' => html_entity_decode( '» ' )
]
The function
function get_taxonomies_terms_links( $args="" ){
global $post;
$defaults = [
'before' => '',
'sep' => '',
'after' => '',
'display_tax_name' => false,
'taxonomy_sep' => ': ',
'multi_tax_sep' => '</br>',
'hierarchical' => true
];
$args = wp_parse_args( $args, $defaults );
$post_type = $post->post_type;
$taxonomies = get_object_taxonomies( $post_type, 'objects' );
$returned_list = [];
foreach ( $taxonomies as $taxonomy_slug => $taxonomy ){
if( $args['hierarchical'] == $taxonomy->hierarchical && has_term( '', $taxonomy_slug ) && 'post_format' != $taxonomy_slug ) {
$term_list = get_the_term_list( $post->ID, $taxonomy_slug, $args['before'], $args['sep'], $args['after'] );
if( true == $args['display_tax_name'] ){
$returned_list[] = strtoupper($taxonomy_slug) . $args['taxonomy_sep'] . $term_list;
}else{
$returned_list[] = $term_list;
}
}
}
if( $returned_list ) {
$count = count($returned_list);
if( 1 === $count ) {
return implode( '', $returned_list );
}else{
$multi_list = [];
foreach ( $returned_list as $key=>$value ) {
if (array_key_exists($key + 1, $returned_list)) {
$multi_list[] = $value . $args['multi_tax_sep'];
}else{
$multi_list[] = $value;
}
}
return implode( '', $multi_list );
}
}
}
Example of use in a template to display the term list. You can either make use of the normal reading characters or HTML entities in conjunction with html_entity_decode() and the character chart
Arguments as string
<span class="cat-links">
<?php echo get_taxonomies_terms_links('sep=, &display_tax_name=" . true ."&taxonomy_sep=' . html_entity_decode( '» ' ) ); ?>
</span>
Arguments as an array
<span class="cat-links">
<?php
echo get_taxonomies_terms_links(
[
'sep' => ', ',
'display_tax_name' => true,
'taxonomy_sep' => html_entity_decode( '» ' )
],
);
?>
</span>