Counting multiples of three and filling empty slots with alternate content - php

Question

I am displaying a listing of TV shows on a website in rows with three columns per row. When I do not have enough shows in multiples of three, I want to fill the empty slots with alternate content.
The code I am using to display the listing is:
<?php $counter = 1; ?>
<?php foreach ($show_listingsRecords as $record): ?>
<?php if($counter % 3 == 0) : ?>
<!-- ROW 3 -->
<div> ... display name + description + link ...</div>
<?php elseif ($counter % 3 == 2) : ?>
<!-- ROW 2 -->
<div> ... display name + description + link ...</div>
<?php elseif ($counter % 3 == 1): ?>
<!-- ROW 1 -->
<div> ... display name + description + link ...</div>
<?php endif; ?>
<?php $counter++; ?>
<?php endforeach ?>
I've tried to insert the following conditional statement, but it does not work because the foreach() loop dictates the number of records to be displayed. How do I achieve displaying alternate content if slots 2 or 2 & 3 are empty?
<?php if(!$show_listingsRecords): ?>
Display my alternate content
<?php endif ?>

Answer 1

I would recommend doing all of the processing first and then only using foreach() to display it.
The first step is checking what kind of modification is needed to prepare your $show_listingsRecords array.
If there are no subarrays, then you will need to use all three $alternates subarrays.
If the number of subarrays does not evenly divide by $chunk_size (number of subarrays per batch), then merge only the necessary amount of subarrays from $alternates to complete the "batch".
Code: (Demo)
$show_listingsRecords=array(
array("name"=>1,"description"=>2,"link"=>3),
array("name"=>4,"description"=>5,"link"=>6),
array("name"=>7,"description"=>8,"link"=>9),
array("name"=>10,"description"=>11,"link"=>12),
array("name"=>13,"description"=>14,"link"=>15)
);
$alternates=array(
array("name"=>"backup1A","description"=>"backup1B","link"=>"backup1C"),
array("name"=>"backup2A","description"=>"backup2B","link"=>"backup2C"),
array("name"=>"backup3A","description"=>"backup3B","link"=>"backup3C") // needed if no listings at all
);
$chunk_size=3; // 3 is used in this case
// conditionally prepare array
if(!$size=sizeof($show_listingsRecords)){ // if no listings at all (empty array)
$show_listingsRecords=$alternates;
}elseif($over=$size%$chunk_size){ // $over is how many extra elements beyond "even" (0,1,2 in this case)
$show_listingsRecords=array_merge($show_listingsRecords,array_slice($alternates,0,$chunk_size-$over));
}
// display
foreach(array_chunk($show_listingsRecords,$chunk_size) as $batch){ // iterate in batches
echo "<div>\n";
foreach($batch as $listing){ // iterate the arrays in the batch
echo "\t<div>",implode(' + ',$listing),"</div>\n";
}
echo "</div>\n";
}
Output:
<div>
<div>1 + 2 + 3</div>
<div>4 + 5 + 6</div>
<div>7 + 8 + 9</div>
</div>
<div>
<div>10 + 11 + 12</div>
<div>13 + 14 + 15</div>
<div>backup1A + backup1B + backup1C</div>
</div>

Answer 2

You could add another loop after your code:
//As long as there is some remainder
while($counter % 3) {
//add desired content
switch($counter++ % 3) {
case 1: break;
case 2: break;
}
}
A would also suggest you use a constant/variable instead of magic number 3. If you decide to use 4 columns in the future all you need to do is change the variable and add conditions for the fourth column instead of manually checking and rewriting the "correct" numbers 3 (find and replace could change number 3 in other part of your code you do not want to change).