如何在没有自定义帖子类型类别的情况下获取所有帖子类别？

Question

I am creating a Blog in wordpress.

I have a list of categories: Technology, Art, fashion, Home, Lifetime, Education, Business, Religion, Design and home, Marketing

In which some of these categories I am using only in Custom Post Type (Technology, Art, Fashion) and others only in Normal Posts (Home, Life, Education, Business, Religion, Design and home, Marketing).

Now I need to get the list of categories that are only being used from normal posts to show them on my blog (). I tried to do the following but it returns all categories including CPTs:

$categories = get_categories();
foreach($categories as $category) {
    echo '<li class="cat-name"  . '>' . $category->name . '</li>';
}

I just need to show the categories: Home, Life, Education, Business, Religion, Design & Home, Marketing.

And exclude those that are being used in CPT. Please Help!

Answer 1

You need to pass in the arguments and exclude the term_ids or include on the term_ids you want. You can use one of the following: 'exclude', 'exclude_tree', or 'include'.

$args = array(
        'taxonomy' => 'category', 
        'exclude' => array(65,23,98,23,78), // term_ids you want to exclude
        'exclude_tree' => (65,23,98,23,78), // term_ids you want to exclude and their descendants/children
        'include' => (11,51,90,57,29), // only the term_ids you want to include
        'orderby' => 'name',
        'order' => 'ASC',
        "hide_empty" => 1,
    );
    $cats = get_categories($args);
    foreach ($cats as $cat){
        echo $cat_slug = $cat->slug;
    }

'include'

Array or comma/space-separated string of term IDs to include. Default empty array.

'exclude'

Array or comma/space-separated string of term IDs to exclude. If $include is non-empty, $exclude is ignored. Default empty array.

'exclude_tree'

Array or comma/space-separated string of term IDs to exclude along with all of their descendant terms. If $include is non-empty, $exclude_tree is ignored. Default empty array.

Learn more about all the arguments you can pass to get_categories() or get_terms() , get_posts() etc https://developer.wordpress.org/reference/classes/wp_term_query/__construct/

Try WP_Query if the above isn't working

$args = array(
   'tax_query' => array(
        array(
           'taxonomy' => 'category',
           'field' => 'slug',
           'terms' => array( 'home', 'life', 'education', 'business', 'religion', 'design-and-home', 'marketing' ),
           'operator' => 'IN'
        ),
        array(
           'taxonomy' => 'custom_taxonomy_registerd_to_cpt_slug', // again make sure in your cpt plugin that this taxonomy is unique and not just 'category'
           'field' => 'slug',
           'terms' => array( 'technology', 'art', 'fashion' ),
           'include_children' => false,
           'operator' => 'NOT IN'
        )
    )
);
$cats = new WP_Query($args);
foreach ($cats as $cat){
    print_r($cat); // use this to find the values you need. Remove after you build the link html
}

Answer 2

This function with shortcode is tested and work for me

 <?php 
        function list_categories_func($atts) {
        $a = shortcode_atts( array('' => '',), $atts );
        $args = array('taxonomy'=>'category','parent'=>0,'orderby'=>'name','order'=>'ASC', 'hide_empty'=>0,);
        $categories=get_categories($args);
        echo "<ul>";
        foreach($categories as $category){
        $name=$category->slug;
        echo "<li>$id</li>";
        }
        echo "</ul>";
        $output = ob_get_contents();
        ob_end_clean();
        return $output;
        }
        add_shortcode( 'ni_categories_row', 'list_categories_func' );
    ?>