De duplicate multidimensional array

Question

I have a fairly simple multidimensional array that I need to dedupe. I also need to remove any key that has a value, so in the below code I would need to keep the second target/value of city/Paris (Array 3) and also remove the 6th Array.


Array
(
    [0] => Array
        (
            [target] => city
            [value] => London
        )

    [1] => Array
        (
            [target] => colour
            [value] => Red
        )

    [3] => Array
        (
            [target] => city
            [value] => Paris
        )

    [4] => Array
        (
            [target] => type
            [value] => House
        )

    [6] => Array
        (
            [target] => name
            [value] => 
        )

    [7] => Array
        (
            [target] => email
            [value] => mail@gmail.com
        )

    [9] => Array
        (
            [target] => custom2
            [value] => path/to/something
        )

)

I can do this by:

Flattening the array
Assigning the target/value as new key/values (this automatically overwrites the later value if there are dupes)
Remove any keys that have a value of
Rebuild the array

This feels wrong and I'm sure there is a better solution using array_walk_recursive() as this would probably preserve the original keys and make for a more elegant solution.

This is my current code:

function _clean_and_dedupe_targeting($array) {
  // First flatten the array.
  $flattenned = array();
  foreach ($array as $item) {
    foreach ($item as $value) {
      $flattenned[] = $value;
    }
  }

  // Take alternate items as key/value pairs.
  // THIS WILL OVERWRITE ANY DUPLICATES LEAVING THE ONE SET IN CONTEXT IN PLACE.
  $keyval = array();
  array_unshift($flatenned, false);
  while (false !== $key = next($flattenned)) {
    $keyval[$key] = next($flattenned);
  }

  // Remove any items with <REMOVE>
  $remove_string = '<REMOVE>';
  $remove_keys = array_keys($keyval, $remove_string);

  // Remove any keys that were found.
  foreach ($remove_keys as $key) {
    unset($keyval[$key]);
  }

  // Rebuild the array as a multidimensional array to send to the js.
  $targeting = array();
  $i = 0;
  foreach ($keyval as $target => $value) {
    $targeting[$i] = array('target' => $target, 'value' => $value);
    $i++;
  }

  return $targeting;
}

Possible duplicate of http://stackoverflow.com/questions/2442230/php-getting-unique-values-of-a-multidimensional-array — Ben Carey, Jan 29 '13 at 11:34
possible duplicate of [php multi-dimensional array remove duplicate](http://stackoverflow.com/questions/1861682/php-multi-dimensional-array-remove-duplicate) — Kuf, Jan 29 '13 at 13:44

score 0 · Answer 1 · answered Jan 29 '13 at 13:22

Your algorithm is exactly what you would do:

// flatten and remove empty values
$params = array();
foreach ($values as $value) {
    if (!empty($value['value'])) {
        $params[$value['target']] = $value['value'];
    }
}

// rebuild array
$values = array();
foreach ($params as $target => $value) {
    $values[] = array(
        'target' => $target,
        'value' => $value,
    );
}

De duplicate multidimensional array

1 Answers1