Wordpress 页面分页 IF 查询

Question

<?php
$pagelist = get_pages('sort_column=menu_order&sort_order=asc');
$pages = array();
foreach ($pagelist as $page) {
   $pages[] += $page->ID;
}

$current = array_search(get_the_ID(), $pages);
$prevID = $pages[$current-1];
$nextID = $pages[$current+1];
?>

<div id="page_nav">
	<div class="wrapper">
		<a href="<?php echo get_permalink($prevID); ?>"><i class="fa fa-arrow-left"></i>Previous Work</a><span>/</span>
		<a id="back_link" href="http://kyleskelly.co.uk/#projects_container">Back to Projects</a><span>/</span>
		<a href="<?php echo get_permalink($nextID); ?>">Next Work<i class="fa fa-arrow-right"></i></a>
	</div>
</div>

我对php的了解不是很好，如果有任何帮助，将不胜感激，谢谢！

我希望我的代码能够查询 -

IF 是投资组合中的第一页，然后上一个链接的 a 标记无效。

else if 作品集中的最后一页，则下一页链接无效。

else我已有的代码

Answer 1

我没有尝试过这段代码，但我认为它应该可以工作。如果出现问题，请告诉我。我已经对代码进行了注释，以或多或少地向您解释我所做的事情。

<?php
$pagelist = get_pages('sort_column=menu_order&sort_order=asc');
$current = get_the_ID();// Current Page ID. I assume IDs are unique, and all pages have one. All the IDs are in $pagelist.

$next = $prev = FALSE;
reset($pagelist);// Pointer to first element.
while ($page = current($pagelist) ){// Loop through the array. I used while instead of foreach for its convenience to get next element.
    if( $page->ID == $current) {
        $obj = next($pagelist);
        $next = $obj ? $obj->ID : FALSE;// If there's a next, get the ID, otherwise we are the last page.
        break;
   }

   $prev = $page->ID;// Previous element
   next($pagelist);// Update pointer
}

?>

<div id="page_nav">
    <div class="wrapper">
        <?php if($prev !== FALSE) {// If I have a previous element, print out a ?>
        <a href="<?php echo get_permalink($prev); ?>"><i class="fa fa-arrow-left"></i>Previous Work</a><span>/</span>
        <?php } ?>
        <a id="back_link" href="http://kyleskelly.co.uk/#projects_container">Back to Projects</a><span>/</span>
        <?php if($next !== FALSE) {// If I have a next element, print out a ?>
        <a href="<?php echo get_permalink($next); ?>">Next Work<i class="fa fa-arrow-right"></i></a>
        <?php } ?>
    </div>
</div>