list all images of a folder with php

images.php

<?php

// list all images of a folder
$folder = 'images/';
$types = array('png','jpg','jpeg','gif');
$openfolder = opendir($folder);

while ($file = readdir($openfolder))
{
	if( in_array(strtolower(substr($file,-3)),$types) OR
	  in_array(strtolower(substr($file,-4)),$types) )
	{
		$array[] = $file;
	}
}

echo '<ul>';
 
$number = count($array);
shuffle($array);
for($i=0; $i<$number; $i++)
{
	echo '<li><img src="'.$folder.$array[$i].'" /></li>';
}

echo '</ul>';

?>