// File JScript
function sajax(url, onload, parameters, onerror)
{
	parameters = (parameters == undefined)? "" : parameters;
	
	//creazione oggetto per richiesta web
	var objHTTP = getXMLHttp();
	objHTTP.open("post", url, true);
	objHTTP.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
	objHTTP.setRequestHeader('Content-length',parameters.length);
	objHTTP.setRequestHeader('Connection', 'close');

	objHTTP.onreadystatechange = function() 
	{ 
		if (objHTTP.readyState == 4) 
		{
			if (objHTTP.status == 200 || objHTTP.status == 0)
			{
				this.request = objHTTP;
				if(onload) onload.call(this);
			}											
			else {if(onerror && typeof(onerror) == "function") {onerror(defaultError); return;}else {defaultError(); return;}}
		}
	};

    objHTTP.send(parameters);
    

    function getXMLHttp() 
    {
	    var xmlhttp = null;
    	
	    if(window.XMLHttpRequest) 
	    {
		    xmlhttp = new XMLHttpRequest(); // Gecko (Firefox, Moz), KHTML (Konqueror, Safari), Opera, Internet Explorer 7
	    } 
	    else if(window.ActiveXObject) 
	    {
		    try
		    {
			    xmlhttp = new ActiveXObject("MSXML2.XMLHTTP"); // Internet Explorer 6 
		    } 
		    catch(e) 
		    {
			    xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); // Internet Explorer 4,5 
		    }
		    } 
	    else 
	    {
		    xmlhttp = null;
	    }
	    return xmlhttp;
    };

	function defaultError()
	{
		alert("ERRORE NELLA TRASMISSIONE DATI!");
	};
}

//al posto di mettere document.getElementById("div1"), mettere $("div1")
//da prototype.js
function $() {
  var elements = new Array();

  for (var i = 0; i < arguments.length; i++) {
    var element = arguments[i];
    if (typeof element == 'string')
      element = document.getElementById(element);

    if (arguments.length == 1)
      return element;

    elements.push(element);
  }

  return elements;
}