- serialize: documentation ( source)
<?php
echo serialize(array('docs' => array(array('property_imgurl' => 'http://www.example.com/image1.jpg'), array('property_imgurl' => 'http://www.example.com/image2.jpg'), array('property_imgurl' => 'http://www.example.com/image3.jpg'), array('property_imgurl' => 'http://www.example.com/image4.jpg'))));