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

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