php explode and foreach returens only one loop - php

Question

I am not very professional but
I have this PHP code :
$m = mysqli_query($dblink,"select * from bot where type='movie' and ID ='$wait'");
while($a = mysqli_fetch_array($m, MYSQLI_ASSOC)){
$ex = explode(",",$a["links"]);
preg_match_all('/\b(https?|ftp|file):\/\/[-A-Z0-9+&##\/%?=~_|$!:,.;]*[A-Z0-9+&##\/%=~_|$]/i', $ex[1], $matches);
$urls = $matches[0];
foreach($urls as $url){
$s=size($url);
}
preg_match_all('/\b(https?|ftp|file):\/\/[-A-Z0-9+&##\/%?=~_|$!:,.;]*[A-Z0-9+&##\/%=~_|$]/i', $ex[1], $matches2);
$urls2 = $matches2[0];
}
and I also have http://site1.com,http://site2.com,http://site3.com in my "links" column of database.
so here is my problem : the code only shows one of the sites.
I was wondering if the problem is with foreach or explode or non of them?
thank all of you in advance!
EDIT :
so I changed my code to this :
$ex = explode(",",$a["links"]);
$url=$a["links"];
foreach($ex as $url){
$s=size($url);
...
}
and it seems to be a problem with $url because when I use a custom url for example http://test.com instead of $url it works and shows me 3 links which is the number of links in my database with the url of http://test.com.
What am I doing wrong with $url ?

Answer 1

$ex = explode(",",$a["links"]);
Will return an array of values (links) as follows:
$ex[0] = 'http://site1.com'
$ex[1] = 'http://site2.com'
$ex[2] = 'http://site3.com'
And you are passing only the second position of the array (index = 1 => $ex[1]) to the next line
preg_match_all('/\b(https?|ftp|file):\/\/[-A-Z0-9+&##\/%?=~_|$!:,.;]*[A-Z0-9+&##\/%=~_|$]/i', $ex[1], $matches);
so, you can do this:
foreach($ex as $url) {
preg_match_all('/\b(https?|ftp|file):\/\/[-A-Z0-9+&##\/%?=~_|$!:,.;]*[A-Z0-9+&##\/%=~_|$]/i', $url, $matches);
}
to get the matches for each url in the links database column