Why is my preg_match_all not working?

Question

I am using preg_match_all to ensure that a string follows a certain pattern.

It should display 'all conditions are met' becuase the string follows the pattern, but instead, it displays 'conditions net met'.

$order = "item[]=2&item[]=1&item[]=3&item[]=4&item[]=5&item[]=6&item[]=7&item[]=8&item[]=9&item[]=10&item[]=11&item[]=12";
$pattern = "/^(item\[\]=([1-9]|10|11|12))(&(item\[\]=([1-9]|10|11|12))){11}$/";

if(preg_match($pattern, $order)) {

   // check for repetition
   $matches = [];
   preg_match_all("/\d+/", $order, $matches);
   if(count(array_count_values($matches[0])) == 12) {
      // All are unique values
      echo 'All conditions met';
   }
}else{
   echo 'Conditions not met';
}

Answer 1

The right way would be using
parse_str(to parse quesry string: key/value pairs separated with &)
and array_diff(to check if all numbers from the needed range 1-12 are present and not repeated) functions:

$order = "item[]=2&item[]=1&item[]=3&item[]=4&item[]=5&item[]=6&item[]=7&item[]=8&item[]=9&item[]=10&item[]=11&item[]=12";
parse_str($order, $items);

if (isset($items['item']) && is_array($items['item'])
    && count($items['item']) == 12 && !array_diff(range(1, 12), $items['item'])) {
    echo 'All conditions met';
} else {
    echo 'Conditions not met';
}