function ck_login(nomeform)
{
	document.getElementById('error_log').style.display='none';
	
	var username = document.formlogin.user_log.value;
	var password = document.formlogin.psw_log.value;
	
	if((username=="") || (password==""))
	{
		document.getElementById('error_log').style.display='block';
		document.getElementById('error_log').innerHTML='Username e/o password non validi';
		blink_form_twins();
	}
	else
	{
		creaQueryString_b(nomeform);
	}
}




function creaQueryString_b(queryform)
{
	var stringa="";
	var frm = document.forms[queryform];
	var numeroElementi = frm.elements.length;
	
	for(var x = 0; x<numeroElementi; x=x+1)
	{
		if(x<numeroElementi-1)
		{
			if((frm.elements[x].name!="") && (frm.elements[x].name!=undefined))
			{
				
				stringa +=frm.elements[x].name+"="+encodeURIComponent(frm.elements[x].value)+"&";
				
			}
		}
		else
		{
			if((frm.elements[x].name!="") && (frm.elements[x].name!=undefined==true))
			{
			
				stringa +=frm.elements[x].name+"="+encodeURIComponent(frm.elements[x].value);
				
			}
		}
	}
	
	send_data_b(stringa,queryform);
	
}


var xmlHttp = getXmlHttpObject();


function send_data_b(dati)
{
		xmlHttp.open('POST', 'sendlogin_ajax.php', true);
		xmlHttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
		xmlHttp.onreadystatechange = stateChangeds_b; 
														
		xmlHttp.send(dati);

}




function stateChangeds_b() {



	if(xmlHttp.readyState == 4) 
	{
	
		//Stato OK
		if (xmlHttp.status == 200) 
		{
			
			var risp = xmlHttp.responseText;

			if(risp!="")
			{
				risp=risp.replace(/^\s*/gi,"");
				
				
				if(risp=='no_log')
				{
					document.location.href="no_log.php";
				}
				else if(risp=='assente')
				{
					document.getElementById('error_log').style.display='block';
					document.getElementById('error_log').innerHTML='Username e/o password non validi';
					blink_form_twins();
				}
				else
				{
					document.getElementById('col_ajax').innerHTML=risp;
					document.location.href="index.php";
				}
				
			}
			
		} 
		else 
		{
			alert(xmlHttp);
		}
	}
}


function getXmlHttpObject()
{
  var xmlHttp=null;
  try
    {
    // Firefox, Opera 8.0+, Safari
    xmlHttp=new XMLHttpRequest();
    }
  catch (e)
    {
    // Internet Explorer
    try
      {
      xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
      }
    catch (e)
      {
      xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
      }
    }
  return xmlHttp;
}