how to get youtube embed code using php code example

Example 1: php convert link to embed youtube

function convertYoutube($string) {
    return preg_replace(
        "/\s*[a-zA-Z\/\/:\.]*youtu(be.com\/watch\?v=|.be\/)([a-zA-Z0-9\-_]+)([a-zA-Z0-9\/\*\-\_\?\&\;\%\=\.]*)/i",
        "<iframe src=\"//www.youtube.com/embed/$2\" allowfullscreen></iframe>",
        $string
    );
}

Example 2: php get embed code from youtube url

preg_replace("/\s*[a-zA-Z\/\/:\.]*youtube.com\/watch\?v=([a-zA-Z0-9\-_]+)([a-zA-Z0-9\/\*\-\_\?\&\;\%\=\.]*)/i","<iframe width=\"420\" height=\"315\" src=\"//www.youtube.com/embed/$1\" frameborder=\"0\" allowfullscreen></iframe>",$post_details['description']);