Loop through php multi level associative array

Question

I am struggling to return values from all layers of a multidimensional array, e.g. value then all child elements. I've tried lots of loops but can't quite get it right. Please can someone help - I've been stuck for ages! Thank you.

The array is:

Array
(
    [SiteRep] => Array
        (   [DV] => Array
                (
                    [Location] => Array
                        (
                            [Period] => Array
                                (
                                    [0] => Array
                                        (
                                            [value] => 2016-12-19Z
                                            [Rep] => Array
                                                (
                                                    [0] => Array
                                                        (
                                                            [D] => W
                                                            [F] => 1
                                                            [G] => 9
                                                        )

                                                    [1] => Array
                                                        (
                                                            [D] => W
                                                            [F] => 0
                                                            [G] => 7
                                                        )

                                                )
                                        )

                                    [1] => Array
                                        (
                                            [value] => 2016-12-20Z
                                            [Rep] => Array
                                                (
                                                    [0] => Array
                                                        (
                                                            [D] => ENE
                                                            [F] => 4
                                                            [G] => 7

                                                        )

                                                    [1] => Array
                                                        (
                                                            [D] => E
                                                            [F] => 3
                                                            [G] => 9

                                                        )

so far my code is:

$i=0;
    foreach ($json_decoded['SiteRep']['DV']['Location']['Period'][$i] as $key => $value) {
    if (is_array($value)){
        foreach ($value as $key2 => $value2){
            if (is_array($value2)){
                foreach ($value2 as $key3 => $value3) {
                    echo $key3 . " 3: " . $value3 . "<br>";
                }
            } else {
                echo $key2 . " 2: " . $value2 . "<br>";
            }
        };

    } else {
        echo $key . " 1: " . $value . "<br>";
    }
    $i++;
};

Answer 1

I believe you are looking for recursion. A function that calls itself. It can be tricky but it is by far the most efficient way to navigate an array of indeterminate depth.

function printStuff($stuff)
{
  echo $stuff['value']
  if (isset($stuff['rep']))
  {
    printStuff($stuff['rep']);
  }
}

If you want the values to pass down simply change echo to a return value:

function printStuff($stuff)
{
  $temp = $stuff['value']
  if (isset($stuff['rep']))
  {
    $temp .= printStuff($stuff['rep']);
  }
  return $temp;
}

Note: recursion can cause out of memory if not set up correctly similar to an infinite loop, as the recursive function call pushes the function call onto the call stack every time. Just make sure your function call has a subset of the parameter passed in.