function printData(data)
{
  if(data == "0")
	{
	  var div_info = document.getElementById("info");
	  div_info.style.fontFamily = "Arial, bold";
	  div_info.style.paddingLeft = "10px";
	  div_info.style.paddingTop = "10px";
	  div_info.style.paddingBottom = "10px";
	  div_info.style.color = "#006600";
	  div_info.style.fontSize = "14px";
	  div_info.style.borderStyle = "solid";
	  div_info.style.borderColor = "#006600";
	  div_info.innerHTML = "Il messaggio e' stato inviato correttamente ... grazie.";
	  div_info.style.display = "block";
	}
	else if(data == "1")
	{
		var div_info = document.getElementById("info");
		  div_info.style.fontFamily = "Arial, bold";
		  div_info.style.paddingLeft = "10px";
		  div_info.style.paddingTop = "10px";
		  div_info.style.paddingBottom = "10px";
		  div_info.style.color = "#990000";
		  div_info.style.fontSize = "14px";
		  div_info.style.borderStyle = "solid";
		  div_info.style.borderColor = "#990000";
		  div_info.innerHTML = "Si e' verificato un errore nell' invio, riprovare piu' tardi ... grazie.";
		  div_info.style.display = "block";
	}

}

function getFormRequest(objform)
{
  var params = new Array();
  
  for(var i = 0; i < objform.elements.length; i++)
  {
    var sp = encodeURIComponent(objform.elements[i].name);
    sp += "=";
    sp += encodeURIComponent(objform.elements[i].value);
    params.push(sp);
  }
  
  return params.join("&");
}

function controlFields()
{
	var errormessage = "";
	var nome = document.getElementById("nome");
	if(nome.value.length <= 0)
		errormessage += "il campo " + nome.id + " e' vuoto\n";
	var cognome = document.getElementById("cognome");
	if(cognome.value.length <= 0)
		errormessage += "il campo " + cognome.id + " e' vuoto\n";
	var email = document.getElementById("email");
	if(email.value.length <= 0)
		errormessage += "il campo " + email.id + " e' vuoto\n";	
	var mesg = document.getElementById("messaggio");
	if(mesg.value.length <= 0)
		errormessage += "il campo " + mesg.id + " e' vuoto\n";
	
	return errormessage;	
}

function sendForm()
{
	// codice AJAX

	var emesg = controlFields();
	if(emesg.length > 0)
		alert(emesg);
	else
	{
		var oForm = document.forms[0];
		var querystr = getFormRequest(oForm);
		
		var objXml = zXmlHttp.createRequest();
		objXml.open("POST",oForm.action,true);
		objXml.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
		objXml.onreadystatechange = function()
		{
		  if(objXml.readyState == 4)
		  {
			if(objXml.status == 200)
			  printData(objXml.responseText);
			else
			  printData(objXml.responseText);
		  }
		};
		objXml.send(querystr);
	}
}