Exception #0 (Exception): Warning: explode() expects parameter 2 to be string, array given in

Question

Exception #0 (Exception): Warning: explode() expects parameter 2 to be string, array given in /home/user/public_html/app/code/Mageplaza/LayeredNavigation/Plugin/Model/Adapter/Preprocessor.php on line 92

the code

 if (($filter->getField() === 'category_ids')) {
 $filterValue = implode(',', array_map([$this, 'validateCatIds'], explode(',', $filter->getValue())));

Answer 1

Check the value for the $filter->getValue() using $filter->getValue()??''.

Your code should be:

$filterValue = implode(',', array_map([$this, 'validateCatIds'], explode(',', $filter->getValue()??'')));

Answer 2

Please modify your code like below

if (($filter->getField() === 'category_ids')) {
 $value = $filter->getValue();
 if (is_array($value)) {
 $filterValue = implode(',', array_map([$this, 'validateCatIds'], $value));
 } else {
 $filterValue = implode(',', array_map([$this, 'validateCatIds'], explode(',', $value)));
 }
}