Wordpress获取发布的类别尝试了wordpress文章

I am trying get the post by its category in WordPress i have category section in my panel and i have added the category as English but when i try to supply that in the array is see no change when added category attribute when category_name is added it return nothing

$book = array(
    'post_type' => 'book',
    'paged'=> $paged,
     'category'         => 'English',
    'category_name'    => 'English',
     'posts_per_page'         => '12'
);

Category parameters work only for default WordPress posts. With custom post types you must use tax_query.

new WP_Query( array(
    'post_type' => 'book',
    'tax_query' => array(
        array (
            'taxonomy' => 'your_custom_taxonomy_slug_here',
            'field' => 'slug',
            'terms' => 'english',
        )
    ),
) );

https://codex.wordpress.org/Class_Reference/WP_Query#Taxonomy_Parameters

Try to use this code:

$book = array(
  'post_type'      => 'book',
  'paged'          => $paged,
  'category_name'  => 'english',
  'posts_per_page' => 12,
);
$query = new WP_Query( $book );

There is no parameter called 'category'. All category parameters:

• cat (int) - use category id.
• category_name (string) - use category slug.
• category__and (array) - use category id.
• category__in (array) - use category id.
• category__not_in (array) - use category id.

So, if you use 'category name' query get the posts that have these categories, using category slug.

For more details see this link to Wordpress Codex

Try this

$custom_terms = get_terms('english');

foreach($custom_terms as $custom_term) {
    wp_reset_query();
    $args = array('post_type' => 'book',
        'tax_query' => array(
            array(
                'taxonomy' => 'english',  //The name of the taxonomy. Name should be in slug form (must not contain capital letters or spaces). 
                'field' => 'slug',
                'terms' => $custom_term->slug,
            ),
        ),
     );

     $loop = new WP_Query($args);
     print_r($loop);die;
     if($loop->have_posts()) {
        echo '<h2>'.$custom_term->name.'</h2>';

        while($loop->have_posts()) : $loop->the_post();
            echo '<a href="'.get_permalink().'">'.get_the_title().'</a><br>';
        endwhile; 
     }
}

Note that The name of the taxonomy. Name should be in slug form (must not contain capital letters or spaces).

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