3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $string = '<iframe width="640" height="360" src="http://www.youtube.com/embed/h9jOaIB1VGo?rel=0&wmode=transparent" frameborder="0" allowfullscreen></iframe>'; preg_match("#(?<=v=)[a-zA-Z0-9-]+(?=&)|(?<=v\/)[^&\n]+(?=\?)|(?<=v=)[^&\n]+|(?<=youtu.be/)[^&\n]+#", $string, $matches); var_dump($matches);
Output for 4.3.0 - 7.1.0
array(0) { }