I wanted to assign a returned value (just text) to a variable in jQuery. I wrote this:

 var hm=22;

   $.ajax({
       type: "GET",
       url: "ajax_check_match.php",                                                     
       dataType: "text",
       success:callback
       });

  function callback(data, status)
    {   
           // assign ajaxed value to cm variable                                                
    cm=data;

    if (hm != cm)
    {
    dosomething();
    }
     }

But it fails every time. Why is that the cm variable keeps getting undefined when it sends request. I set the php file to return 1 and it still says undefined. I opened ajax_check_match.php in browser and I see "1".

I didn't see the point of using XML or JSON since a simple number would suffice. Or do I have to use XML/JSON?