Swap all youtube urls to embed via preg_replace() - php

Question

Hello I'm trying to convert youtube links into embed code.
this is what I have:
<?php
$text = $post->text;
$search = '#<a(.*?)(?:href="https?://)?(?:www\.)?(?:youtu\.be/|youtube\.com(?:/embed/|/v/|/watch?.*?v=))([\w\-]{10,12}).*$#x';
$replace = '<center><iframe width="560" height="315" src="http://www.youtube.com/embed/$2" frameborder="0" allowfullscreen></iframe></center>';
$text = preg_replace($search, $replace, $text);
echo $text;
?>
It works for one link. However if I add two, it will only swap the last occurrence. What do I have to change?

Answer 1

You're not handling the end of the string properly. Remove the $, and replace it with the closing tag </a>. this will fix it.
$search = '#<a(.*?)(?:href="https?://)?(?:www\.)?(?:youtu\.be/|youtube\.com(?:/embed/|/v/|/watch?.*?v=))([\w\-]{10,12}).*<\/a>#x';
$replace = '<center><iframe width="560" height="315" src="http://www.youtube.com/embed/$2" frameborder="0" allowfullscreen></iframe></center>';
$text = preg_replace($search, $replace, $text);

Answer 2

Try this : preg_replace($search, $replace, $text, -1);
I know it's the default but who knows...
EDIT Try that if not working ;
do{
$text = preg_replace($search, $replace, $text, -1, $Count);
}
while($Count);

Answer 3

Here are a regular expresion more efficient: http://pregcopy.com/exp/26, tralate this to PHP: (add "s" modifier)
<?php
$text = $post->text;
$search = '#<a (?:.*?)href=["\\\']http[s]?:\/\/(?:[^\.]+\.)*youtube\.com\/(?:v\/|watch\?(?:.*?\&)?v=|embed\/)([\w\-\_]+)["\\\']#ixs';
$replace = '<center><iframe width="560" height="315" src="http://www.youtube.com/embed/$1" frameborder="0" allowfullscreen></iframe></center>';
$text = preg_replace($search, $replace, $text);
echo $text;
?>
Test it

Answer 4

There are two types of youtube link for one video:
Example:
$link1 = 'https://www.youtube.com/watch?v=NVcpJZJ60Ao';
$link2 = 'https://www.youtu.be/NVcpJZJ60Ao';
This function handles both:
function getYoutubeEmbedUrl($url)
{
$shortUrlRegex = '/youtu.be\/([a-zA-Z0-9_-]+)\??/i';
$longUrlRegex = '/youtube.com\/((?:embed)|(?:watch))((?:\?v\=)|(?:\/))([a-zA-Z0-9_-]+)/i';
if (preg_match($longUrlRegex, $url, $matches)) {
$youtube_id = $matches[count($matches) - 1];
}
if (preg_match($shortUrlRegex, $url, $matches)) {
$youtube_id = $matches[count($matches) - 1];
}
return 'https://www.youtube.com/embed/' . $youtube_id ;
}
The output of $link1 or $link2 would be the same :
$output1 = getYoutubeEmbedUrl($link1);
$output2 = getYoutubeEmbedUrl($link2);
// output for both: https://www.youtube.com/embed/NVcpJZJ60Ao
Now you can use the output in iframe!