How to read PHP variable from JavaScript?

Question

I know that there are many questions about this but I cannot make it work.

My HTML (test.htm) has only this code

<?php
$var = 'foo';
?>
<script type="text/javascript" language="javascript">
var val = "<?=$var?>";
alert(val);
</script>

But when I open the file with the browser the value of val is "<?=$var?>" and not 'foo'

How can I make it work?

Answer 1

Unless you have some configuration to allow it, .htm files won't execute PHP code, you'll have to use a .php file.

If you look at your HTML page source in the browser, you'll probably see all the PHP code.

The only other explanation is that short tags <? ?> aren't enabled, you'll have to use
<?php echo $var; ?>