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

What's wrong with this code?

Here is the quiz. "Next, modify the code inside the foreach loop to display both the $title and the $isbn. After the title, add a space, an opening parenthesis, the ISBN, and a closing parenthesis, like this: Gilgamesh (978-0743261690)"

and here is my code. and the error message is " The ISBN numbers should appear in parenthesis following the corresponding title."

output.html is as follows:

Five Great Books

Notice: Undefined variable: title in index.php on line 20 (978-0743261690) Notice: Undefined variable: title in index.php on line 20 (978-0060931957) Notice: Undefined variable: title in index.php on line 20 (978-0192840509) Notice: Undefined variable: title in index.php on line 20 (978-0520227040) Notice: Undefined variable: title in index.php on line 20 (978-0393320978)

index.php
<?php

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

?><html>
<head>
    <title>Five Great Books</title>
</head>
<body>
    <h1>Five Great Books</h1>
    <ul>
        <?php foreach($books as $isbn=>$book) { ?>
         <li><?php echo  $title. " ". '('. $isbn . ')'; ?></li>



        <?php } ?>
    </ul>
</body>
</html>

2 Answers

The problem is here: <?php echo $title. " ". '('. $isbn . ')'; ?> There is no $title variable. Instead use $book, the variable created in your foreach loop.

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

Thank you very much. :)