我用this solution, 但是，我想过滤更多内容，只显示与主帖子类别匹配的自定义帖子类型中的帖子（或者更准确地说是slug，但解决方案没有区别）。

我使用以下方法获得主帖子的slug：

$category_main = get_the_category();
$cat_slug = $category_main[0]->slug;
echo $cat_slug; // This is just to see if I got the right output

我以同样的方式从自定义post类型中获取slug，但它在一个循环中，循环通过自定义post类型。

$category_course = get_the_category();
$cat_slug_course = $category_course[0]->slug;
echo $cat_slug_course;

所以，我现在想要的是，只显示自定义类型中与原始帖子的slug匹配的帖子。

在伪代码中，这类似于：

If $cat_slug_course is equal to $cat_slug, display all custom type posts with slug $cat_slug_course and none other

这是用于显示自定义类型帖子的循环。

$args = array( \'post_type\' => \'Course\', \'posts_per_page\' => 2 );
$loop = new WP_Query( $args );
while ( $loop->have_posts() ) : $loop->the_post();

    $category_course = get_the_category();
    $cat_slug_course = $category_course[0]->slug;
    echo $cat_slug_course; // This is just to see if I got the right output
    echo \'<br />\';    
    the_title();
    echo \'<div class="entry-content">\';
    the_content();
    echo \'</div>\';
endwhile; ?>

$category_main = get_the_category();
$cat_slug = $category_main[0]->slug;
// echo $cat_slug; // This is just to see if I got the right output
$args = array( 
  \'post_type\' => \'Course\', 
  \'posts_per_page\' => 2,
  \'category_name\' => $cat_slug,
);
$loop = new WP_Query( $args );
while ( $loop->have_posts() ) {
  $loop->the_post();

  $category_course = get_the_category();
  $cat_slug_course = $category_course[0]->slug;
  //   echo $cat_slug_course; // This is just to see if I got the right output
  echo \'<br />\';    
  the_title();
  echo \'<div class="entry-content">\';
  the_content();
  echo \'</div>\';
}

<?php if ($cat_slug_course == $cat_slug): ?>
    <div class="landing_title">
        <?php the_title(); ?>
    </div>
        <?php the_content();?>
    </div>
<?php endif; ?>