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<?php $blogPostWord = 'http://youtu.b/O7Lm3BMG8ow'; preg_match('#(?<=v=)[a-zA-Z0-9-]+(?=&)|(?<=v\/)[^&\n]+(?=\?)|(?<=v=)[^&\n]+|(?<=youtu.be/)[^&\n]+#', $blogPostWord, $matches); var_dump($matches);

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