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PHP Build a Simple PHP Application Integrating with PayPal Array Keys


Next, modify the code inside the foreach loop to display the $isbn in parentheses. After the title, add a space, an opening parenthesis, the ISBN, and a closing parenthesis.


$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>
        <?php foreach($books as $isbn => $book) { ?>
            <li><?php echo $book . '('. $ISBN .')'; ?></li>
        <?php } ?>

1 Answer

Im not exactly sure what issue your having but I assume its not letting you progress. PHP is a case sensitive language so $ISBN != $isbn they are considered separate variables. Its also not a good idea to use all capital letters unless it is a constant variable.

        <?php foreach($books as $book => $isbn) : ?>
            <li><?php echo $book . '('. $isbn .')'; ?></li>
        <?php endforeach; ?>

This should get you what you're after. I re-ordered your key value pairs on the for each loop to match the data.