//Function to Make request to server
function makeHttpRequest(url, callback_function, return_xml) 
{ 
    var http_request, response, i; 
    var activex_ids = ['MSXML2.XMLHTTP.3.0','MSXML2.XMLHTTP','Microsoft.XMLHTTP']; 
    
    if (window.XMLHttpRequest) { // Mozilla, Safari, IE7+... 
       http_request = new XMLHttpRequest(); 
       if (http_request.overrideMimeType) { 
         http_request.overrideMimeType('text/xml'); 
       } 
     } 
     else if (window.ActiveXObject) { // IE6 and older 
        for (i = 0; i < activex_ids.length; i++) { 
            try
            { 
                http_request = new ActiveXObject(activex_ids[i]); 
            } 
            catch (e) {} 
   } 
 } 
 
 if (!http_request) { 
   alert("Unfortunately your browser doesn't support this feature."); 
   return false; 
 } 
 
 //Function onreadystatechange
 http_request.onreadystatechange = function() { 
   if (http_request.readyState !== 4) { 
       // not ready yet 
       return; 
   } 
   if (http_request.status !== 200) { 
     // ready, but not OK 
     alert('There was a problem with the request.(Code: ' + http_request.status + ')'); 
     return; 
   } 
   if (return_xml) { 
     response = http_request.responseXML; 
   }
   else{ 
     response = http_request.responseText; 
   }

   // invoke the callback 
   callback_function(response); 
 }; 
 
 http_request.open('GET', url, true); 
 http_request.send(null); 
}