Multidimensional loop on two CSV file php - php

Question

I need to compare two CSV file that both contain two columns: ID and URL and check if the URL are differents. The two file normally, are the same but sometimes it can change. So i have to compare if the ID is the same and if the URL has change. I would like do this with a multidimensional loop (both of files are very big). But i don't understand why at the first match, the loop is stopped.
I try to do this with a while loop:
while ($file_odierno_fr = fgetcsv($product_dinamica_fr, 0, ";", '"')) {
while ($file_precedente_fr = fgetcsv($product_dinamica_fr_pre, 0, ";", '"' )) {
// the index [1] is the URL and ID is the index [0]
if ($file_odierno_fr[1] !== $file_precedente_fr[1] && $file_odierno_fr[0] == $file_precedente_fr[0]){
$textMail .= "\n\nURL file odierno: <b>".$file_odierno_fr[1]. "</b>\nURL file pecedente: <b>". $file_precedente_fr[1] . "</b>\n\n";
fputcsv($file,array($file_odierno_fr[1], $file_precedente_fr[1]),";");
$sendMail = TRUE;
}
}
}
fclose($product_dinamica_fr);
fclose($product_dinamica_fr_pre);
But when igo to debug this, i get juste the first match and the rest is ignored. I change some URL in the file for be sure that all is working.
I think that i can't do while loop like this, but i'm not sure. There is a way for do that with while loop?

Answer 1

Please try to following code and give a feedback:
$separator = ";";
$enclosure = '"';
$lineSize = 0;// 0 := unlimited
$textMail = "";
while($lineNow = fgetcsv($product_dinamica_fr, $lineSize, $separator, $enclosure))
{
while($linePre = fgetcsv($product_dinamica_fr_pre, $lineSize, $separator, $enclosure))
{
$idNow = trim($lineNow[0]);
$idPre = trim($linePre[0]);
$urlNow = trim($lineNow[1]);
$urlPre = trim($linePre[1]);
// Compare IDs first. If they are not the same, then skip this line
if($idNow != $idPre)
continue;
// If URLs are the same then skip this line
if( $urlNow == $urlPre)
{
continue;
}
// Set email flag and add info to e-mail content
$sendMail = TRUE;
$textMail .= "\n\nURL file odierno: <b>$urlNow</b>\nURL file pecedente: <b>$urlPre</b>\n\n";
// Write the difference to local file
fputcsv($file, [$urlNow, $urlPre], ";");
}
rewind($product_dinamica_fr_pre);
}
fclose($product_dinamica_fr);
fclose($product_dinamica_fr_pre);
echo $textMail;