How to convert simple_html_dom object back to string?

I have used [PHP Simple HTML DOM Parser][1] to first convert an HTML string to DOM object by `str_get_html()` method of simple_html_dom.php $summary = str_get_html($html_string); 1. Then I extracted an `<img>` object from the `$summary` by foreach ($summary->find('img') as $img) { $image = $img; break; } Now I needed to convert $image DOM object back to a string. I used the [Object Oriented way mentioned here][2]: $image_string = $image->save(); **I got the error (from the *Moodle debugger*):** > Fatal error: Call to undefined method simple_html_dom_node::save() ... 2. So I thought since I am working with Moodle, it may have something to do with Moodle, so I simply did the simple (non-object oriented?) way [from the same manual][3]: $image_string = $image; Then just to check/confirm that it has been converted to a string, I did: echo '$image TYPE: '.gettype($image); echo '<br><br>'; echo '$image_string TYPE: '.gettype($image_string); **But this prints:** $image TYPE: object $image_string TYPE: object **So the question is Why??? Am I doing something wrong?** [1]: http://simplehtmldom.sourceforge.net/manual.htm [2]: http://simplehtmldom.sourceforge.net/manual.htm#container_dump [3]: http://simplehtmldom.sourceforge.net/manual.htm