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

11,675 Points

how to access the key from array.

Difficulty in accessing array keys.


$books["978-0743261690"] = "Gilgamesh";
$books["978-0060931957"] = "The Odyssey";
$books["978-0192840509"] = "Aesop's Fables";
$books["978-0520227040"] = "Mahabharta";
$books["978-0393320978"] = "Beowulf";
$isbn = $get_id
    <title>Five Great Books</title>
    <h1>Five Great Books</h1>
        <?php foreach($books as $book) { ?>
            <li><?php echo $book; ?></li>
        <?php } ?>

2 Answers

Joe Scotto
Joe Scotto
8,282 Points

To access the key from an array within a loop you can use a key assigned to a value like this:

foreach($books as $key => $book) { ?>
    echo $key; 

The $key will always refer to the key of that current iteration in the loop, the $book will refer to the value.

Ricky Johnston
Ricky Johnston
27,445 Points

I think you could be looking for the PHP key() function. http://php.net/manual/en/function.key.php

In this example, if you were using key(), your code would look like

<?php foreach($books as $book) { ?>
            <li><?php echo key($book); ?></li>
<?php } ?>

And your output would be