How do I pass variables and data from PHP to JavaScript

Question

I have a variable in PHP, and I need its value in my JavaScript code. How can I get my variable from PHP to JavaScript?

I have code that looks like this:

<?php
     ...
     $val = $myService->getValue(); // Makes an API and database call
?>

I have JavaScript code that needs val and looks along the lines of:

<script>
    myPlugin.start($val); // I tried this, but it didn't work
    <?php myPlugin.start($val); ?> // This didn't work either
    myPlugin.start(<?=$val?> // This works sometimes, but sometimes it fails
</script>

Answer 1

Hello @kartik,

Simply use one of the following methods.

<script type="text/javascript">
var js_variable  = '<?php echo $php_variable;?>';
<script>

OR

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

Hope it helps!!

Thank you!