get php variable by a javascript variable

Question

I've got 4 PHP variables, and I have 1 Javascript variable with the name of one of those 4 PHP variables, how can reference it?

$p1 = ...
$p2 = ...
$p3 = ...
$p4 = ...

<script>
    var myoption = 'p1';
    var myarray = <?= $p1 ?>;
    console.log(myarray);
</script>

In this case instead of setting myarray to $p1, I want to do it with myoption, once myoption can be p2 or p3

If myoption is going to be set dynamically in js then you'll have to use something like ajax to get the value of the variable you want. — Musa
– Musa, Commented Jan 8, 2022 at 16:23
got it, and for example can I set the js variable to a php function return? — tiago calado
– tiago calado, Commented Jan 8, 2022 at 16:24
You need to understand what runs at what point, first PHP is run / executed / interpreted, then the result of the php file is returned to the client where the JavaScript may be executed. — luk2302
– luk2302, Commented Jan 8, 2022 at 16:32
yes, in this case the php variable is already set, I just need what is there, has the same order that above — tiago calado
– tiago calado, Commented Jan 8, 2022 at 16:42
When, where, and how does myoption vary? Please edit your question to show more specifics. — kmoser
– kmoser, Commented Jan 8, 2022 at 18:26

Lajos Arpad · Accepted Answer · 2022-01-09 02:00:09Z

1

You can create a PHP array, json_encode it into your Javascript, like this:

$p1 = ...
$p2 = ...
$p3 = ...
$p4 = ...

$myPHPArray = [
    'p1' => $p1,
    'p2' => $p2,
    'p3' => $p3,
    'p4' => $p4
];

<script>
    var myoption = 'p1';
    var myarray = <?php echo json_encode($myPHPArray) ?>;
    console.log(myarray[myoption]);
</script>

answered Jan 9, 2022 at 2:00

Lajos Arpad

80.3k42 gold badges122 silver badges234 bronze badges

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

Collectives™ on Stack Overflow

get php variable by a javascript variable

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related