Add tr after 4 uploaded images - php

Question

I want a gallery of uploaded images, showing 4 images each tr.
There needs to be a loop somewhere but I can't get it to work.
It needs to add a tr automatically when there are 4 images in a tr.
<?php
$folder = 'uploads/';
$filetype = '*.*';
$files = glob($folder.$filetype);
$count = count($files);
$sortedArray = array();
for ($i = 0; $i < $count; $i++) {
$sortedArray[date ('YmdHis', filemtime($files[$i]))] = $files[$i];
}
krsort($sortedArray);
echo '<table>';
foreach ($sortedArray as &$filename) {
echo '<td align="center">';
echo '<a name="'.$filename.'" href="#'.$filename.'"><img src="'.$filename.'" /></a>';
echo 'Bestand naam: ' . substr($filename,strlen($folder),strpos($filename, '.')-strlen($folder));
echo '</td>';
}
echo '</table>';
?>

Answer 1

Let a counter, say $i run alongside your foreach loop that ticks up by one every time the loop ran. Check for "every fourth element" with if ($i % 4 ==0)

Answer 2

Use a counter in your loop. It should look like this :
echo '<table>';
$ctr = 0;
foreach ($sortedArray as &$filename) {
echo ($ctr % 4 == 0) ? "<tr>" : "";
echo '<td align="center">';
echo '<a name="'.$filename.'" href="#'.$filename.'"><img src="'.$filename.'" /></a>';
echo 'Bestand naam: ' . substr($filename,strlen($folder),strpos($filename, '.')-strlen($folder));
echo '</td>';
$ctr++;
echo ($ctr % 4 == 0) ? "</tr>" : "";
}
echo '</table>';

Answer 3

<?php
$folder = 'uploads/';
$filetype = '*.*';
$files = glob($folder . $filetype);
$count = count($files);
$sortedArray = array();
$i = 0;
krsort($sortedArray);
echo '<table><tr>';
foreach($sortedArray as & $filename)
{
echo '<td align="center">';
echo '<a name="' . $filename . '" href="#' . $filename . '"><img src="' . $filename . '"/> </a>';
echo 'Bestand naam: ' . substr($filename, strlen($folder) , strpos($filename, '.') - strlen($folder));
echo '</td>';
if ($i % 4 == 0)
{
echo '</tr><tr>';
}
$i++;
}
echo '</tr></table>';
?>