Cómo usar la variable JavaScript en PHP
<script>
var p1 = "success";
</script>
<?php
echo "<script>document.writeln(p1);</script>";
?>
Adventurous Anteater
<script>
var p1 = "success";
</script>
<?php
echo "<script>document.writeln(p1);</script>";
?><script type="text/javascript">
// boolean outputs "" if false, "1" if true
var bool = "<?php echo $bool ?>";
// numeric value, both with and without quotes
var num = <?php echo $num ?>; // 7
var str_num = "<?php echo $num ?>"; // "7" (a string)
var str = "<?php echo $str ?>"; // "A string here"
</script>
<?php
$color = "Red";
?>
<script type="text/javascript">var color = "<?= $color ?>";</script>
<script type="text/javascript" src="file.js"></script>