Convert php array to Javascript

Question

How can I convert a PHP array in a format like this

Array
(
    [0] => 001-1234567
    [1] => 1234567
    [2] => 12345678
    [3] => 12345678
    [4] => 12345678
    [5] => AP1W3242
    [6] => AP7X1234
    [7] => AS1234
    [8] => MH9Z2324
    [9] => MX1234
    [10] => TN1A3242
    [11] => ZZ1234
)

to a Javascript array in the format below?

var cities = [
    "Aberdeen",
    "Ada",
    "Adamsville",
    "Addyston",
    "Adelphi",
    "Adena",
    "Adrian",
    "Akron",
    "Albany"
];

Solution 1

Spudley's answer is fine.

Security Notice: The following should not be necessary any longer for you

If you don't have PHP 5.2 you can use something like this:

function js_str($s)
{
    return '"' . addcslashes($s, "\0..\37\"\\") . '"';
}

function js_array($array)
{
    $temp = array_map('js_str', $array);
    return '[' . implode(',', $temp) . ']';
}

echo 'var cities = ', js_array($php_cities_array), ';';

Solution 2

I'm going to assume that the two arrays you've given for PHP and JS are not related, and they're just examples of how arrays look in the two languages. Clearly you're not going to be able to convert those sequences of letters and numbers into those city names.

PHP provides a function to convert PHP arrays into Javascript code: json_encode(). (technically, it's JSON format; JSON stands for JavaScript Object Notation)

Use it like this:

<script type='text/javascript'>
<?php
$php_array = array('abc','def','ghi');
$js_array = json_encode($php_array);
echo "var javascript_array = ". $js_array . ";\n";
?>
</script>

See also the manual page I linked above for more information.

Note that json_encode() is only available in PHP 5.2 and up, so if you're using an older version, you'll need to use an existing one -- the PHP manual page also includes comments with functions written by people who needed it. (but that said, if you're using anything older than PHP 5.2 you should upgrade ASAP)

Solution 3

Dumb and simple :

var js_array = [<?php echo '"'.implode('","', $php_array).'"' ?>];

Solution 4

You do not have to call parseJSON since the output of json_encode is a javascript literal. Just assign it to a js variable.

<script type="text/javascript">
    //Assign php generated json to JavaScript variable
    var tempArray = <?php echo json_encode($php_array); ?>;

   //You will be able to access the properties as 
    alert(tempArray[0].Key);
</script>

Solution 5

you can convert php arrays into javascript using php's json_encode function

<?php $phpArray = array(
          0 => 001-1234567, 
          1 => 1234567, 
          2 => 12345678, 
          3 => 12345678,
          4 => 12345678,
          5 => 'AP1W3242',
          6 => 'AP7X1234',
          7 => 'AS1234',
          8 => 'MH9Z2324', 
          9 => 'MX1234', 
          10 => 'TN1A3242',
          11 => 'ZZ1234'
    )
?>

<script type="text/javascript">

    var jArray= <?php echo json_encode($phpArray ); ?>;

    for(var i=0;i<12;i++){
        alert(jArray[i]);
    }

 </script>

View more solutions

Comments

[T.J. Crowder]

Can you clarify your question? Are you really trying to create a JavaScript array, or are you trying to create a string you can put in a script tag that will create it, or are you trying to create JSON to send back in reply to an ajax request, or... (Also, worth checking out the How to Format box on the right-hand side when you're asking your question, and the page linked from the [?] just above the question area.)

[Daniel Sloof]

You're missing a semicolon at the end of the javascript array, and also that's not the way PHP arrays are initialized (try array('abc'....))... upvote anyway because its probably what OP wants

[Spudley]

agreed: if you're using and old PHP, you'll need to write your own. However, you should also consider upgrading your PHP if at all possible!

[hakre]

Even if you're using old PHP, don't write your own, take an existing library that is maintained / used by more than one person/project. So this answer is only showing how something could be done, but it should not recommend this - regardless of the PHP version. E.g. pear.php.net/package/Services_JSON

[Udo G]

You're right. However, the code above has been used/tested for years in two large projects.

[hakre]

php.net/array_map - and implode uses values only so already ignoring keys.

[Udo G]

Yes, that's intentional. Check the original question.

[Udo G]

BTW, you added the array_map call. And, honestly, there is no need to edit a perfectly valid answer to the original question and mark it with a "Security Notice" when it doesn't incur any security issues.

[Spudley]

@UdoG: if you disagree with an edit, you are free to edit it again yourself. hakre has a point that it would be sensible for someone reading this question to use a library that was known to be secure and well tested, eg from Pear rather than just taking this code on merit. Also, it's worth pointing out that PHP 5.2 was already out of support when this question was asked. As I write now, it has been unsupported for two years and has known security issues that will not be patched. It is therefore a security issue simply to be using PHP 5.2, before we even consider the code in this answer.

[user3871]

@Spudley Hi, I tried this, and in the javascript tried accessing the array created in php as such console.log('stuff: ' + javascript_array[0]);, but it says javascript_array has not been defined

[Nis]

Just out of curiosity: what would happen when string contains quote , double quotes and/or comma?

[Ben Rogmans]

If your PHP array contains special characters, this will go wrong. You can escape special characters using urlencode() functions. See my answer: stackoverflow.com/questions/5618925/…

[Spudley]

@BenRogmans - PHP's json_encode() function does work with UTF-8 characters. If you're having an issue with it, then it's more likely that you've got other parts of your system in the wrong encoding that need to be changed - the output of json_encode() shouldn't need any additional encoding; that's kinda the whole point.

[cjbarth]

Since there is a function for this, that should be preferred over an improvised solution unless there is a good reason; no reason is herein stated.

[Fr0zenFyr]

Without doubt, the best approach to what OP wanted. I was wondering if JSON object really is same as an array... I mean consider a situation where I want to check if a value exists in my array and do jsonEncodedObject.indexOf( 'my string' ) > -1, it will most likely throw an error. For this to work, jsonEncodedObject should be an array of the form ['my string', 'a string', 'some string', 'other string' ]. I tried it and the result was as I expected.

[Eric]

that loop is terrible

[Dipesh KC]

Well that was for demonstration purpose :)

[Dipesh KC]

@Eric the example was directly taken as it is from the question. I could have used console.log() but the question itself is very basic (and user many not have experience with the browser code inspect tool ), so I decided to go with alert() since the user will see it directly.But you know it very well it is not the concerned part of the question, just a way to verify if the logic works or not.

[Heitor]

Please nevermind!! Now we can just use this: json_encode($array, JSON_PRETTY_PRINT); and be happy!

[Patrick Moore]

Just to point out that json_encode define a JavaScript object, NOT an array.

[Spudley]

@PatrickMoore - if you're going to be pedantic about it, json_encode outputs a JSON string, which can represent either a JS object or a JS array, or even a single scalar value, if that's what you pass it. The examples in my answer will output a JavaScript array, not an object.

[oldboy]

is it insecure to simply swap over the values (i.e. echo "jsArray.push(\"" . $result[$i]["column_name"] . "\");";) ??????

[Hammad Khan]

works better for unicode characters (urdu in my case)

[Tomas Crofty]

The method @MohammadKawsara used works best for me obviously if you trust the user data.

[Peter Lenjo]

...or you could implode() the first array to get the "fake" one. I know this is an old response, but the idea just crossed my mind.

[Mik]

sure, but my way is the fastest of all suggestions on this page. Sometimes, speed could be an important factor.

[A. D'Alfonso]

Already upvoted this in 2018... I'd like to upvote again but can't

[Bi Wu]

Thanks, this worked well even for mixed object array. Very simple and efficient!