How to Retrieve First Level Keys in a 2D Array Using a Foreach Loop in PHP?

Using a Foreach Loop to Retrieve First Level Keys in a 2D Array

In PHP, iterating through a multidimensional array can be tricky, especially when it comes to accessing its first level keys. Let's delve into a practical scenario and demonstrate how to achieve this using a foreach loop.

You have an array named $places with a structure like this:

[Philadelphia] => Array
    (
        [0] => Array
            (
                [place_name] => XYX
                [place_id] => 103200
                [place_status] => 0
            )

        [1] => Array
            (
            [place_name] => YYYY
            [place_id] => 232323
            [place_status] => 0
        )
    )

Your code currently looks like this:

foreach($places as $site): ?>
    <h5><?=key($site)?></h5>
        <?php foreach($site as $place): ?>
            <h6><?=$place['place_name']?></h6>
        <?php endforeach?>

<?php endforeach ?>

You aim to retrieve the first level key (e.g., "Philadelphia") when you call key($site), but it's currently returning the second level key ("place_name").

To resolve this issue, you need to access the first level key directly, which is straightforward in PHP:

foreach ($places as $key => $value)

In this code, $key will be the first level key, and $value will represent the corresponding array for that key.

Here's a revised code:

foreach ($places as $key => $site): ?>
    <h5><?= $key ?></h5>
        <?php foreach($site as $place): ?>
            <h6><?=$place['place_name']?></h6>
        <?php endforeach?>

<?php endforeach ?>

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