声明使用PHP显示foreach输出的顺序

Question

I am currently trying to set up a custom sortable list. Without getting into too much detail as this would become a very large post, I would like to use the PHP foreach function to show the list.

I currently have

$video_id = $row['videos'];
  $res = preg_replace("/[^0-9,.]/", "",$video_id);
$exclude = explode(',', $res);
} ?>

....

<ul id="sortable2" class="connectedSortable">
<?php foreach ($video_list as $key => $item): ?>
<?php if(in_array($item['id'], $exclude)){ ?>
<li id="video-<?php echo $item['id'] ?>"><?php echo $item['id'], 
$item['title'] ?></li>
<?php } ?>
<?php endforeach; ?>
</ul>

This generates a list of items from the database excluding items with an ID from an array which is also fetched from another table.

In this example, it will only show videos with the id 3,4 and 2. This is all working as expected. My issue is once I have reordered the items and refreshed the page they are loaded in numerical order. I need these to be load in the order specified (3,4 and 2 for this example).

Any help would be highly appreciated.

Thanks

Answer 1

I think what you are looking for is ORDER BY FIELD (MySql), this lets you order by a field in a specific way.

I need these to be load in the order specified (3,4 and 2 for this example).

Sounds like a good fit to me!

For example

   SELECT * FROM table WHERE id IN(3,4,2) ORDER BY FIELD(id, 3,4,2)

This will select rows from table where the id is in the list and then order the results by id in the order they are place there, 3 then 4 then 2.

excluding items with an ID

This might cause some issue, the Field order by assumes you know at least some of the values in the field. Excluding implies that you know what you don't want but not necessarily what you do want, if that makes sense.

Maybe it's not an issue, I don't have enough information on your particular use case to determine that, so I am just mentioning it as a cautionary thing.

Thanks!