function createRequestObject() {
    var tmpXmlHttpObject;

    if (window.XMLHttpRequest) { 
        // Mozilla, Safari
        tmpXmlHttpObject = new XMLHttpRequest();
	
    } else if (window.ActiveXObject) { 
        // IE
        tmpXmlHttpObject = new ActiveXObject("Microsoft.XMLHTTP");
    }
    
    return tmpXmlHttpObject;
}

function makeGetRequest(url, func) {
    http = createRequestObject();
    http.open('get', url);
	
    http.onreadystatechange = function() {
      if(http.readyState == 4){
        var response = http.responseText;
        window[func](response);
      }
    }

    http.send(null);
}