PHP function to get recursive path keys with path

Question

Given an array, I would like a flattened version of the array keys. Each array key would need the 'path' of the array, to that point, appended with an underscore.

An example explains this best.

$arr = array("location"=>0,"details"=>array("width"=>0,"height"=>0,"level"=>array("three"=>0)));

function answer($arr) {....}

the answer function would return this:

array("location","details_width","details_height","details_level_three");

UPDATE:

Here is the work in progress. It will accept an array and return the array keys, but with no depth:

function recursive_keys($input)
{
    $output = array_keys($input);
    foreach($input as $sub){
        if(is_array($sub)){
            $output = array_merge($output, recursive_keys($sub));
        }
    }
    return $output;
}

I have a set of functions that can successfully traverse a multidimensional array, and return all the array keys . But I don't know how to append the current 'path' as I am traversing the array. — user1082428
– user1082428, Commented Dec 5, 2011 at 22:21

goat · Accepted Answer · 2011-12-05 22:59:52Z

7

$ritit = new RecursiveIteratorIterator(new RecursiveArrayIterator($arr));
$results = array();
foreach ($ritit as $leafValue) {
    $path = array();
    foreach (range(0, $ritit->getDepth()) as $depth) {
        $path[] = $ritit->getSubIterator($depth)->key();
    }
    $results[] = join('_', $path);
}

answered Dec 5, 2011 at 22:59

goat

31.9k7 gold badges76 silver badges98 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Antonio E. Over a year ago

+1 For the idea, anyway if you are dealing with empty arrays (as I did) this solution is not complete because the RecursiveArrayIterator cannot recognize the 'leaves'. To make it work with leaves array that are empty you can use a class similar to this:

class RecursiveArrayOnlyIterator extends RecursiveArrayIterator {     public function hasChildren() {         return is_array($this->current()) && (count($this->current())>0);     } }

Reference: php.net

goat Over a year ago

@AntonioE. you could also just use the RecursiveIteratorIterator::SELF_FIRST arg for the RecursiveIteratorIterator constructor(then it will visit all nodes, not just leaves). But, you will get many partial, less than full paths as a result.

deceze · Accepted Answer · 2011-12-05 22:54:21Z

2

function recursive_keys(array $array, array $path = array()) {
    $result = array();
    foreach ($array as $key => $val) {
        $currentPath = array_merge($path, array($key));
        if (is_array($val)) {
            $result = array_merge($result, recursive_keys($val, $currentPath));
        } else {
            $result[] = join('_', $currentPath);
        }
    }
    return $result;
}

Demo here: http://codepad.viper-7.com/WQ3UYI

answered Dec 5, 2011 at 22:54

deceze♦

525k89 gold badges806 silver badges954 bronze badges

3 Comments

user1082428 Over a year ago

Excellent, this is what I need! To your code, I added if(!is_array($val)) right before the if(!is_array($val)) line as I dont' want to add a key if it's value is an array.

giannis.epp Over a year ago

I use if (is_array($val) && $val) instead of if (is_array($val)) to get it work in my case

mickmackusa Over a year ago

@deceze this demo link has died. This answer could also use some explanation.

Collectives™ on Stack Overflow

PHP function to get recursive path keys with path

2 Answers 2

2 Comments

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related