Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

PHP Build a Basic PHP Website (2018) Listing and Sorting Inventory Items Array Keys

Andrew Norris
Andrew Norris
4,857 Points

Stuck on array_keys code challenge in Build a Basic PHP Website module.

I can't seem to get the syntax right to assign the array key from the $books array to a variable named $isbn.


$books["978-0743261690"] = "Gilgamesh";
$books["978-0060931957"] = "The Odyssey";
$books["978-0192840509"] = "Aesop's Fables";
$books["978-0520227040"] = "Mahabharta";
$books["978-0393320978"] = "Beowulf";

    <title>Five Great Books</title>
    <h1>Five Great Books</h1>
    $isbn = array_keys($books);
        <?php foreach($books as $book => $isbn) { ?>
            <li><?php echo $book; ?></li>
        <?php } ?>

1 Answer

Bob McCarty
Bob McCarty
Courses Plus Student 16,618 Points


change the foreach loop from

<?php foreach($books as $book => $isbn) { ?>


<?php foreach($books as $isbn => $book) { ?>
Andrew Norris
Andrew Norris
4,857 Points

Thanks. I had it backwards.