Get YouTube url ID

readme.md

Example code

$link = "https://www.youtube.com/watch?v=sOnqjkJTMaA";
$youtube_ID = get_youtube_ID( $link );

echo $youtube_ID;

<iframe width="560" height="315" src="https://www.youtube.com/embed/<?php echo $youtube_ID; ?>" frameborder="0" allowfullscreen></iframe>

youtube.id.php

<?php
/**
 * Get YouTube url ID
 *
 * @var string $link [ https, m., gaming., www., youtube.com gaming.youtube.com, youtu.be ]
 * @return array $youtube URL && ID
 */

function get_youtube_ID( $link ){
	if( !isset( $link ) || empty( $link ) )
		return;

	preg_match( '/(?:https?:\/\/|www\.|gaming\.|m\.|^)youtu(?:be\.com\/watch\?(?:.*?&(?:amp;)?)?v=|\.be\/)([\w‌​\-]+)(?:&(?:amp;)?[\w\?=]*)?/', $link, $ID );

	$YouTube_ID = isset( $ID[1] ) ? $ID[1] : false;

	return $YouTube_ID;
}