How to pass a jquery variable from one file to another?

Question

I want to pass a jquery variable from page1.php to page2.php. For this, I am using hidden form input method. In page1.php,

<form method="POST" action="page2.php" id="myform">
<input type="hidden" id="myField" name="myFieldName">
</form>

And the value for this input field is getting from a script:

<script>
activeCount = 2; //some value
$("#myField").val(activeCount);
</script>

Now in page2.php,

I cant get the variable printed in page2.php.

In page2.php, I am using the below code:

<?php
  $myfname = $_POST['myFieldName'];
  echo $myfname;   // I cant get this printed.
?>  

Please help. This question is different in the sense, I want to pass the variable from one php file into another, not a js file.