wordpress wp_link_pages同时支持数字与上下页

在wordpress里有个函数wp_link_pages是给文章内容分页的，可是默认的只支持要么显示数字，要么显示下一页按钮，而没有同时显示的，肿么办，将以下代码加入主题的functions.php里即可：

add_filter('wp_link_pages_args', 'wp_link_pages_args_prevnext_add');
function wp_link_pages_args_prevnext_add($args){
 global $page, $numpages, $more, $pagenow;

if (!$args['next_or_number'] == 'next_and_number') 
 return $args; # exit early

$args['next_or_number'] = 'number'; # keep numbering for the main part
 if (!$more)
 return $args; # exit early

if($page-1) # there is a previous page
 $args['before'] .= _wp_link_page($page-1)
 . $args['link_before']. $args['previouspagelink'] . $args['link_after'] . '</a>'
 ;

if ($page<$numpages) # there is a next page
 $args['after'] = _wp_link_page($page+1)
 . $args['link_before'] . '' . $args['nextpagelink'] . $args['link_after'] . '</a>'
 . $args['after']
 ;

return $args;
}

然后，调用：

<?php wp_link_pages( array(<?php wp_link_pages( array( 
'before' => '<div class="page-links">', 
'after'  => '</div>',            
'next_or_number' => 'next_and_number',            
'link_before'      => '<span>',    
'link_after'       => '</span>',            
'nextpagelink'     => 'NEXT',    
'previouspagelink' => 'PREV', ) ); ?>