Hopefully I can ask this correctly cuz I know what I want it to do but can't seem to find any answers from searching.

I have a func.php page where I have all my functions and I want ajax to use one function from that page.

func.php

function toptable()
{ 
  echo"something happens in here";
}

index.php

<?php include 'func.php'; ?>
<script type="text/javascript">
function check_username() {
   uname=document.getElementById("username").value;
   var params = "user_id="+uname;
           var url = "topoftable()";
                $.ajax({
                               type: 'POST',
                               url: url,
                               dataType: 'html',
                               data: params,
                               beforeSend: function() {
                                 document.getElementById("right").innerHTML= 'checking'  ;
                                         },
                               complete: function() {

                               },
                               success: function(html) {

                                      document.getElementById("right").innerHTML= html ;

                                }
                       });

}

</script>

Make sense?