how to do a foreach loop values in a multidimensional array PHP

Question

I'm working with Spotify API and I want to do a foreach loop for only the values in ['tracks'][0]["album"]["images"][2]['url']

How can I go about this?

I tried to do a foreach loop to retrieve value of each key associated inside the multidimensional associative array iterating through each element but can still get it to work.

user_1427345 · Answer

I would approach it like this:

$api = array (
    'tracks' => 
    array (
      0 => 
      array (
        'album' => 
        array (
          'album_type' => 'album',
          'artists' => 
          array (
            0 => 
            array (
              'external_urls' => 
              array (
                'spotify' => 'https://open.spotify.com/artist/4ovtyvs7j1jSmwhkBGHqSr',
              ),
              'href' => 'https://api.spotify.com/v1/artists/4ovtyvs7j1jSmwhkBGHqSr',
              'id' => '4ovtyvs7j1jSmwhkBGHqSr',
              'name' => 'Olamide',
              'type' => 'artist',
              'uri' => 'spotify:artist:4ovtyvs7j1jSmwhkBGHqSr',
            ),
          ),
          'external_urls' => 
          array (
            'spotify' => 'https://open.spotify.com/album/6fG2eFCgUmytQWL6umtsCh',
          ),
          'href' => 'https://api.spotify.com/v1/albums/6fG2eFCgUmytQWL6umtsCh',
          'id' => '6fG2eFCgUmytQWL6umtsCh',
          'images' => 
          array (
            0 => 
            array (
              'height' => '640',
              'url' => 'https://i.scdn.co/image/ab67616d0000b27387d20b9a27d5e14d74b5cb77',
              'width' => '640',
            ),
            1 => 
            array (
              'height' => '300',
              'url' => 'https://i.scdn.co/image/ab67616d00001e0287d20b9a27d5e14d74b5cb77',
              'width' => '300',
            ),
            2 => 
            array (
              'height' => '64',
              'url' => 'https://i.scdn.co/image/ab67616d0000485187d20b9a27d5e14d74b5cb77',
              'width' => '64',
            ),
          ),
          'name' => 'Carpe Diem',
          'release_date' => '2020-10-07',
          'release_date_precision' => 'day',
          'total_tracks' => '12',
          'type' => 'album',
          'uri' => 'spotify:album:6fG2eFCgUmytQWL6umtsCh',
        ),
        'artists' => 
        array (
          0 => 
          array (
            'external_urls' => 
            array (
              'spotify' => 'https://open.spotify.com/artist/4ovtyvs7j1jSmwhkBGHqSr',
            ),
            'href' => 'https://api.spotify.com/v1/artists/4ovtyvs7j1jSmwhkBGHqSr',
            'id' => '4ovtyvs7j1jSmwhkBGHqSr',
            'name' => 'Olamide',
            'type' => 'artist',
            'uri' => 'spotify:artist:4ovtyvs7j1jSmwhkBGHqSr',
          ),
          1 => 
          array (
            'external_urls' => 
            array (
              'spotify' => 'https://open.spotify.com/artist/5yOvAmpIR7hVxiS6Ls5DPO',
            ),
            'href' => 'https://api.spotify.com/v1/artists/5yOvAmpIR7hVxiS6Ls5DPO',
            'id' => '5yOvAmpIR7hVxiS6Ls5DPO',
            'name' => 'Omah Lay',
            'type' => 'artist',
            'uri' => 'spotify:artist:5yOvAmpIR7hVxiS6Ls5DPO',
          ),
        ),
        'disc_number' => '1',
        'duration_ms' => '171764',
        'explicit' => '1',
        'external_ids' => 
        array (
          'isrc' => 'USUYG1330802',
        ),
        'external_urls' => 
        array (
          'spotify' => 'https://open.spotify.com/track/5DS9LiyEdw2zY8bM6kjjgM',
        ),
        'href' => 'https://api.spotify.com/v1/tracks/5DS9LiyEdw2zY8bM6kjjgM',
        'id' => '5DS9LiyEdw2zY8bM6kjjgM
                      [is_local] => ',
        'is_playable' => '1',
        'name' => 'Infinity (feat. Omah Lay)',
        'popularity' => '73',
        'preview_url' => 'https://p.scdn.co/mp3-preview/5159fa17676fc96e32db13b7680f7497d5c2f74d?cid=756f211306ad4c9a934d07c5722790b5',
        'track_number' => '3',
        'type' => 'track',
        'uri' => 'spotify:track:5DS9LiyEdw2zY8bM6kjjgM',
      ),
      1 => 
      array (
        'album' => 
        array (
          'album_type' => 'album',
          'artists' => 
          array (
            0 => 
            array (
              'external_urls' => 
              array (
                'spotify' => 'https://open.spotify.com/artist/4ovtyvs7j1jSmwhkBGHqSr',
              ),
              'href' => 'https://api.spotify.com/v1/artists/4ovtyvs7j1jSmwhkBGHqSr',
              'id' => '4ovtyvs7j1jSmwhkBGHqSr',
              'name' => 'Olamide',
              'type' => 'artist',
              'uri' => 'spotify:artist:4ovtyvs7j1jSmwhkBGHqSr',
            ),
          ),
          'external_urls' => 
          array (
            'spotify' => 'https://open.spotify.com/album/6fG2eFCgUmytQWL6umtsCh',
          ),
          'href' => 'https://api.spotify.com/v1/albums/6fG2eFCgUmytQWL6umtsCh',
          'id' => '6fG2eFCgUmytQWL6umtsCh',
          'images' => 
          array (
            0 => 
            array (
              'height' => '640',
              'url' => 'https://i.scdn.co/image/ab67616d0000b27387d20b9a27d5e14d74b5cb77',
              'width' => '640',
            ),
            1 => 
            array (
              'height' => '300',
              'url' => 'https://i.scdn.co/image/ab67616d00001e0287d20b9a27d5e14d74b5cb77',
              'width' => '300',
            ),
            2 => 
            array (
              'height' => '64',
              'url' => 'https://i.scdn.co/image/ab67616d0000485187d20b9a27d5e14d74b5cb77',
              'width' => '64',
            ),
          ),
          'name' => 'Carpe Diem',
          'release_date' => '2020-10-07',
          'release_date_precision' => 'day',
          'total_tracks' => '12',
          'type' => 'album',
          'uri' => 'spotify:album:6fG2eFCgUmytQWL6umtsCh',
        ),
        'artists' => 
        array (
          0 => 
          array (
            'external_urls' => 
            array (
              'spotify' => 'https://open.spotify.com/artist/4ovtyvs7j1jSmwhkBGHqSr',
            ),
            'href' => 'https://api.spotify.com/v1/artists/4ovtyvs7j1jSmwhkBGHqSr',
            'id' => '4ovtyvs7j1jSmwhkBGHqSr',
            'name' => 'Olamide',
            'type' => 'artist',
            'uri' => 'spotify:artist:4ovtyvs7j1jSmwhkBGHqSr',
          ),
          1 => 
          array (
            'external_urls' => 
            array (
              'spotify' => 'https://open.spotify.com/artist/68R39izwNAztATrXMOqkJS',
            ),
            'href' => 'https://api.spotify.com/v1/artists/68R39izwNAztATrXMOqkJS',
            'id' => '68R39izwNAztATrXMOqkJS',
            'name' => 'Bad Boy Timz',
            'type' => 'artist',
            'uri' => 'spotify:artist:68R39izwNAztATrXMOqkJS',
          ),
        ),
        'disc_number' => '1',
        'duration_ms' => '194000',
        'explicit' => '1',
        'external_ids' => 
        array (
          'isrc' => 'USUYG1330809',
        ),
        'external_urls' => 
        array (
          'spotify' => 'https://open.spotify.com/track/558ULLj8yY2vT8XGtgY0q9',
        ),
        'href' => 'https://api.spotify.com/v1/tracks/558ULLj8yY2vT8XGtgY0q9',
        'id' => '558ULLj8yY2vT8XGtgY0q9
                      [is_local] => ',
        'is_playable' => '1',
        'name' => 'Loading (feat. Bad Boy Timz)',
        'popularity' => '64',
        'preview_url' => 'https://p.scdn.co/mp3-preview/7848a9f9ea879e6b1c6618508354e2559678aa8c?cid=756f211306ad4c9a934d07c5722790b5',
        'track_number' => '10',
        'type' => 'track',
        'uri' => 'spotify:track:558ULLj8yY2vT8XGtgY0q9',
      ),
    ),
);

$tracks = [];

foreach ($api['tracks'] as $track) {
    $_track = [
        'artists' => '',
        'name' => '',
        'album' => '',
        'image' => ''
    ];

    $artists = [];
    foreach ($track['artists'] as $artist) {
        $artists[] = $artist['name'];
    }
    $_track['artists'] = implode(', ', $artists);

    $_track['name'] = $track['name'];
    $_track['album'] = $track['album']['name'];
    $_track['image'] = $track['album']['images'][2]['url'];
    
    $tracks[] = $_track;
}

var_dump($tracks);

Results in:

array(2) {
  [0]=>
  array(4) {
    ["artists"]=>
    string(17) "Olamide, Omah Lay"
    ["name"]=>
    string(25) "Infinity (feat. Omah Lay)"
    ["album"]=>
    string(10) "Carpe Diem"
    ["image"]=>
    string(64) "https://i.scdn.co/image/ab67616d0000485187d20b9a27d5e14d74b5cb77"
  }
  [1]=>
  array(4) {
    ["artists"]=>
    string(21) "Olamide, Bad Boy Timz"
    ["name"]=>
    string(28) "Loading (feat. Bad Boy Timz)"
    ["album"]=>
    string(10) "Carpe Diem"
    ["image"]=>
    string(64) "https://i.scdn.co/image/ab67616d0000485187d20b9a27d5e14d74b5cb77"
  }
}

user_4630325 · Answer

This is conveniently accomplished with array_walk_recursive. It doesn't matter at what depth or position your url key/value is, it will be found and iterated. As follows:

$urls = []; // For collecting URLs, passed in by reference:

array_walk_recursive($data, function($val, $key) use (&$urls) {
    if($key === 'url') { // if $key is "url", add to $urls; ignore the rest.
        $urls[] = $val;
    }
});

Note that if you have multiple url keys at different depths/positions, they will all be added in. If you need to target a specific depth/position where multiple identical keys may exist, the solution would be a bit more complicated. In your use case this is not an issue, so I've kept it simple.

Also note that array_walk_recursive callback function is only called on the "leaves" or the final values of an array. As such, it will not be called on members that are arrays containing arrays. Non-final array members will simply be followed onward until "leaves" are found.

how to do a foreach loop values in a multidimensional array PHP

2 Answers