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![shubhamkt](https://uploads.teamtreehouse.com/production/profile-photos/7142092/micro_treehouse.jpg)
shubhamkt
11,675 Pointshow to access the key from array.
Difficulty in accessing array keys.
<?php
$books["978-0743261690"] = "Gilgamesh";
$books["978-0060931957"] = "The Odyssey";
$books["978-0192840509"] = "Aesop's Fables";
$books["978-0520227040"] = "Mahabharta";
$books["978-0393320978"] = "Beowulf";
$isbn = $get_id
?><html>
<head>
<title>Five Great Books</title>
</head>
<body>
<h1>Five Great Books</h1>
<ul>
<?php foreach($books as $book) { ?>
<li><?php echo $book; ?></li>
<?php } ?>
</ul>
</body>
</html>
2 Answers
![Joe Scotto](https://uploads.teamtreehouse.com/production/profile-photos/6714462/micro_HP5-Door-Reflections.jpg)
Joe Scotto
8,282 PointsTo access the key from an array within a loop you can use a key assigned to a value like this:
foreach($books as $key => $book) { ?>
echo $key;
}
The $key will always refer to the key of that current iteration in the loop, the $book will refer to the value.
![Ricky Johnston](https://uploads.teamtreehouse.com/production/profile-photos/3631442/micro_H74Cops_.jpg)
Ricky Johnston
27,445 PointsI think you could be looking for the PHP key() function. http://php.net/manual/en/function.key.php
In this example, if you were using key(), your code would look like
<?php foreach($books as $book) { ?>
<li><?php echo key($book); ?></li>
<?php } ?>
And your output would be
978-0743261690
978-0060931957
978-0192840509
978-0520227040
978-0393320978