How to set an Array in Javascript dynamically?

Question

I am working on an e-commerce website. There is an array "products" in javascript defined by the following code

<script type="text/javascript">
    var products = 
    [
         {"id":"1","title":"Apple iPhone 4"},
         {"id":"2","title":"BlackBerry 9780 Bold"}
    ];
    /*some other javascript code*/
</script>

I want this array to be updated dynamically according to the number of rows returned by querying the database. For example, suppose I query the database and 5 rows are returned. I want this array to be updated with those 5 rows. Please help me getting this done. I am using PHP, MySQL, Apache on Windows machine.

Is it AJAX or does PHP return a HTML page containing a hard-coded Array? — pimvdb
– pimvdb, Commented Jul 19, 2011 at 18:20

SeanCannon · Accepted Answer · 2011-07-19 18:26:35Z

2

You want the push function: http://www.w3schools.com/jsref/jsref_push.asp

var products = 
[
     {"id":"1","title":"Apple iPhone 4"},
     {"id":"2","title":"BlackBerry 9780 Bold"}
];

// Let's add a new phone:
products.push({"id":"3","title":"HTC Evo"});

/*
    products now equals: 
    [
         {"id":"1","title":"Apple iPhone 4"},
         {"id":"2","title":"BlackBerry 9780 Bold"},
         {"id":"3","title":"HTC Evo"}
    ];
*/

To account for the possibility you may have an existing array and you'd like to update it via ajax, you can do this dynamically with PHP:

<script type="text/javascript">
<?php foreach($phones as $phone): ?>
    products.push({"id":"<?=$phone['id']?>","title":"<?=$phone['name']?>"});
<?php endforeach; ?>
</script>

edited Jul 19, 2011 at 18:26

answered Jul 19, 2011 at 18:20

SeanCannon

78.1k17 gold badges126 silver badges145 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

citizen conn Over a year ago

He's trying to get data from PHP/MySQL over to a Javascript Array, he's not trying to push one javascript element onto a JS Array...

Community · Accepted Answer · 2017-05-23 12:11:55Z

1

The top answer to the question JSON encode MySQL results could achive this for you:

$sth = mysql_query("SELECT ...");
$rows = array();
while($r = mysql_fetch_assoc($sth)) {
    $rows[] = $r;
}

print json_encode($rows);

In your case, replacing the last line with

?>
var products = <?php echo json_encode($rows); ?>;
<?php

would initialize the JavaScript object with your query results. This would need to be done before the page is loaded, because the PHP runs on the server producing the JavaScript for the client. If you need to get the results after the client page is loaded you would need a more complicated solution, probably using AJAX.

edited May 23, 2017 at 12:11

CommunityBot

11 silver badge

answered Jul 19, 2011 at 18:20

user1114

1

Comments

thescientist · Accepted Answer · 2011-07-19 18:20:34Z

0

I would make a server side script that makes the connection to the database, get's the products, and constructs the JSON for you, so that way all you have to do is make an AJAX request to the script from the client side and it will return everything for you for use on your webpage.

answered Jul 19, 2011 at 18:20

thescientist

2,9581 gold badge21 silver badges15 bronze badges

Comments

datasage · Accepted Answer · 2011-07-19 18:20:36Z

0

You can use PHP to output json directly into the page.

Assuming that $data is an array that contains the products you want to output.

In the template you would do something like this:

<script type="text/javascript">
var products =  <?php echo json_encode($data) ?>;
</script>

answered Jul 19, 2011 at 18:20

datasage

19.7k2 gold badges51 silver badges55 bronze badges

Comments

Timur · Accepted Answer · 2011-07-19 18:31:42Z

0

products[products.length] = {..some data..};
products.push({..some data..});

Or you need something else?

answered Jul 19, 2011 at 18:31

Timur

6,7381 gold badge30 silver badges37 bronze badges

Collectives™ on Stack Overflow

How to set an Array in Javascript dynamically?

5 Answers 5

1 Comment

Comments

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

5 Answers 5

1 Comment

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related