The number of WordPress articles within a certain period of time

The number of WordPress articles in a certain period of time, the specific results can be viewed on Wu Leng Blog

function num_posts($days=1) {//$days is the set time day;
 global $wpdb;
 $today = gmdate('Y-m-d H:i:s', time() + 3600 * 8 ); //Get the current time
 $daysago = date( "Y-m-d H:i:s", strtotime($today) - ($days * 24 * 60 * 60) ); //Today - $days
 $result = $wpdb->get_results("SELECT ID FROM $wpdb->posts WHERE post_date BETWEEN '$daysago' AND '$today' AND post_status='publish' AND post_type='post' ORDER BY post_date DESC ");
 foreach ($result as $Item) {
 $post_ID[] = $Item->ID;//Write the published article ID into an array
 }
 $post_num = count($post_ID);// Output the number of elements in the array, the number of article IDs, that is, the number of published articles
 $output .= ''.$post_num.'';//Output the number of articles
 echo $output ;
}