I have a function in JavaScript called message. I want to call this function inside PHP. 
I've tried the following, but it does not work.
<script>
  $(document).ready(function(){
    function JsClass () {  
      this.mensaje = function() {
       alert("You call the JAVASCRIPT FUNCTION IN PHP");`
      }
    }
  });
</script>
<?php               
  function ClasePhp($user, $pw) {
    function callJsFunction() {
  ?>             
    <script>
      var javaClass = new JsClass();
      javaClass.message();
    </script>    
  <?php
    }
  }
?>
