explode() offset and delimiter warnings when delimiter is valid - php

Question

I'm having a heck of a time trying to figure out what is going on. I have a block of code that is throwing some errors. Outside of the Warnings and Notices the code works fine and the arrays are not empty. But why I am getting those warnings and notices is bothersome. In my test environment I don't get the errors however when put on a different server they pop right up. I am stumped as to why. The lines of code that are throwing the errors and the errors being thrown are as follows
$libTitle = explode($libYearRes[0], $value);
Notice: Undefined offset: 0
Warning: explode(): Empty delimiter
$sortLibYearRes = explode(' ', $libYearRes[0]);
Notice: Undefined offset: 0
$libMovieRes = $sortLibYearRes[1];
Notice: Undefined offset: 1
The entire block of code is as follows with the problem lines denoted with a # in them
function checkMovieLibrary($movieTitle,$movieLibrary){
foreach ($movieLibrary as $value) {
preg_match('/\(\d\d\d\d\)\s\d\d\d*[Pp]/', $value, $libYearRes);
$libTitle = #explode($libYearRes[0], $value);
$libMovieTitle = rtrim($libTitle[0]);
$sortLibYearRes = #explode(' ', $libYearRes[0]);
//list($libMovieYear,$libMovieRes) = explode(' ', $libYearRes[0], 2);
$libMovieYear = $sortLibYearRes[0];
$libMovieRes = #$sortLibYearRes[1];
preg_match('/\(\d\d\d\d\)\s\d\d\d*[Pp]/', $movieTitle, $newfileYearRes);
$newFileTitle_array = explode($newfileYearRes[0], $movieTitle);
$newFileTitle = rtrim($newFileTitle_array[0]);
$sortFileYearRes = explode(' ', $newfileYearRes[0]);
$newFileMovieYear = $sortFileYearRes[0];
$newFileMovieRes = $sortFileYearRes[1];
if(stripos($libMovieTitle.' '.$libMovieYear, $newFileTitle.' '.$newFileMovieYear) !== false){
$moviesList_array[] = array('OriginalFile' => $value, 'NewFile' => $movieTitle);
return($moviesList_array);
}
}
return false;
}
//$movieTitle = "10 Cloverfield Lane (2016) 1080p.mkv"; //This is an example of $movieTitle string
//$movieLibrary = array('10 Cloverfield Lane (2016) 1080p.mkv','The Goonies (1985) 1080p.mp4'); this is an example of the $movieLibrary array
$doesMovieExist = checkMovieLibrary($Movie,$movieLibrary);
if(is_array($doesMovieExist) && $doesMovieExist !== false){
foreach($doesMovieExist as $fileKey => $fileValue) {
$originalFile = $fileValue['OriginalFile'];
$newFile = $fileValue['NewFile'];
}
//do some stuff here
}

Answer 1

First of all dont use # because it will bypass the error message. So user error_reporting(E_ALL) till development phase.
Then you are getting undefined offset it means your array is empty of does not exist so put a condition to check if it exist then the explode should work. It must be like that :
if(!empty($libYearRes[0]) || isset($libYearRes[0])) {
$libTitle = #explode($libYearRes[0], $value);
}

Answer 2

Undefined offset error means you're referring an array key that does not exist. If you like to see the array before processing it, use variable dump (var_dump) then you will see these array keys are not available for the given scenario.
you can avoid this error by checking array key really exist or not by using isset function. as example
if(isset($libYearRes[0])){ // will be true only if $libYearRes[0] is exist
$libTitle = explode($libYearRes[0], $value);
}