How can I pass an array from JS to PHP?

Question

Here is my code:

    $(document).on('click', '#csv_export', function () {

        // I need to pass this array to where the form below submits
        var arr = ['item1', 'item2'];

        $('<form action="csv_export/person?filename=export.csv" method="POST"/>')
        .append($('{!! csrf_field() !!}<input type="hidden" name="type" value="save">'))
        .appendTo($(document.body)) //it has to be added somewhere into the <body>
        .submit();
    });

As I've commented in my code, there is arr that I need to pass it to that page the form points out. How can I do that?

Noted that I can putting this in the form:

<input type="hidden" name="arr" value="'+arr+'">

But I it has two problems:

character length limitation
the result will be a string. (while I need an array in the server side)

Possible duplicate of [Pass Javascript Array -> PHP](http://stackoverflow.com/questions/5035547/pass-javascript-array-php) — hassan, Apr 08 '17 at 09:49
@hassan I passed it by setting it as the value of a hidden input. But in this case, there is character length limitation. — Martin AJ, Apr 08 '17 at 09:50
please mention that in your question then, your issue is not in passing javascript array to php, it's in the limitation , right? — hassan, Apr 08 '17 at 09:51
hint: you are not doing anything with `res` and are submitting a hard coded value — charlietfl, Apr 08 '17 at 09:52
The limit on `POST` parameters should be very high. How big is the array? — Barmar, Apr 08 '17 at 10:08
@Barmar Actually I did it first. But it didn't work and I don't know why. — Martin AJ, Apr 08 '17 at 10:12

Barmar · Accepted Answer · 2017-04-08T10:19:39.533

0

Convert the array to JSON with JSON.stringify(). And instead of constructing the input as a string, use a jQuery function to do it:

$('<form action="csv_export/person?filename=export.csv" method="POST"/>')
    .append($('{!! csrf_field() !!}'))
    .append($("<input>", {
        type: 'hidden',
        name: 'arr',
        value: JSON.stringify(arr)
    });
).appendTo('body')
.submit();

In the PHP script, use json_decode($_POST['arr'], true) to get the array.

You should also be able to use AJAX:

$.post('csv_export/person?filename=export.csv', { arr: JSON.stringify(arr) });

For a small array, you could just use { arr: arr } and then access $_POST['arr'] as an array. But when you pass an array like this, each element becomes a separate post parameter, and by default PHP only allows 1000 parameters. You can change this in php.ini, but using JSON is probably a simpler solution for this case.

edited Apr 08 '17 at 10:19

answered Apr 08 '17 at 10:14

Barmar

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Ok, I got the result on the server side. Just the result is a string structured as JSON. Can I get it as an array on the server side? – Martin AJ Apr 08 '17 at 10:38
Got it .. this works as well for me: `(array) json_decode($_POST['arr'], true)` – Martin AJ Apr 08 '17 at 10:42
You don't need `(array)`, `json_decode()` should return an array. – Barmar Apr 08 '17 at 16:15

How can I pass an array from JS to PHP?

1 Answers1