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

Marko Vojvodic
Marko Vojvodic
32,164 Points

explanation for this.....little help:)

explanation for this.....little help:)

if you see my work here could you tell me where im doing wrong,thanks

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 => $book) { ?>
            <li><?php array_key($isbn); ?></li>

        <?php echo $isbn; } ?>
    </ul>
</body>
</html>

2 Answers

Hi there,

In this instance, the $isbn isn't an array, it's the key of the array. When you call the array_key function, you would need to do so on the $books array, i.e. array_key($books) - and in this quiz, I think they don't even want anything that involved, simply some concatenation and variable echoes.

I hope this helps!

Here is the code that should help you get through this challenge:

<?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 $book . "(" . $isbn . ")"; ?></li>
        <?php } ?>
    </ul>
</body>
</html>

The challenge might not require it but there should be a space before the left parenthesis.

" ("

Im still wondering how it is that the code knows that $isbn means the keys . .

It knows because it is identified with the => sign; so:

$x=>$y would output $x as the key value and $y as the stored value in the array in relation to its key.

I hope this helps!