<?php

$post = array();
$post['array1'] = array('info1', 'info2', 'info3');
$post['info4'] = '#';

echo serialize($post);
echo "\n";
echo json_encode($post);

?>

a:2:{s:6:"array1";a:3:{i:0;s:5:"info1";i:1;s:5:"info2";i:2;s:5:"info3";}s:5:"info4";s:1:"#";}
{"array1":["info1","info2","info3"],"info4":"#"}