PHP - Ampersand before the variable in foreach loop [duplicate]

Answer 1

It is used to apply changes in single instance of array to main array..

As:

//Now the changes wont affect array $wishesarray

foreach ($wishesarray as $id => $categoriy) {
      $categoriy++;
}
print_r($wishesarray); //It'll same as before..

But Now changes will reflect in array $wishesarray also

foreach ($wishesarray as $id => &$categoriy) {
      $categoriy++;
}
print_r($wishesarray); //It'll have values all increased by one..