ajax意外令牌*

I have ajax script but it returns unexpected token *. I use ajax example from w3school.com and it different from usually. This is my script:

<script>  
$("#conform").click(function ()
{
   var a= $(this).closest(".col").prev().find("#prod_qty").val();
   var b= $(this).prev().val();
   var c= $(this).closest("#highlight_product").find("#name").val();
   var d= b * c;
   var e= "<?php echo $_SESSION['name'] ?>";
   var f= "<?php echo $_SESSION['email'] ?>";
}
)

    function buy() 
    {   
    xmlHttp=GetXmlHttpObject();
    if (xmlHttp==null)
     {
     alert ('Browser does not support HTTP Request');
     return;
     }
    var url='buy.php?user='+e+'&email='+f+'&product='+c+'&count='+a+'&total='+d;
    xmlHttp.onreadystatechange=stateChanged;
    xmlHttp.open('GET',url,true);
    xmlHttp.send(null);*/
    }

    function stateChanged() 
    { 
    if (xmlHttp.readyState==4 || xmlHttp.readyState=='complete')
     { 
      document.getElementById("txtHint").innerHTML=xmlhttp.responseText;
     }
    }

    function GetXmlHttpObject()
    {
    var xmlHttp=null;
    try
     {
     // Firefox, Opera 8.0+, Safari
     xmlHttp=new XMLHttpRequest();
     }
    catch (e)
     {
     //Internet Explorer
     try
      {
      xmlHttp=new ActiveXObject('Msxml2.XMLHTTP');
      }
     catch (e)
      {
      xmlHttp=new ActiveXObject('Microsoft.XMLHTTP');
      }
     }
    return xmlHttp;

}

I try find it in google, It says problem with dataType, It must HTML. But i dont know how to change it, anyone know?

Can I suggest using Jquery AJAX wrapper? It's cross browser compliant, much neater and lets gives you a handy callback function on completion(really important) since the result is ASYNC which allows you to retrieve data before execution.

$.ajax({
    type: "POST",
    url: '',
    data : '',
    dataType: 'JSON',
    }).done(function(data) {
 // this will be run when the AJAX request completes
    var ParsedData= jQuery.parseJSON(data);
    // this will be run when the AJAX request succeeds
}).fail(function() {
    // this will be run when the AJAX request fails
}).always(function() {
    // this will be run when the AJAX request is complete, whether it fails or succeeds
});

}

The line

xmlHttp.send(null);*/

has unexpected "*/" which needs to be removed

xmlHttp.send(null);