function Left(str, n){
	if (n <= 0)
	    return "";
	else if (n > String(str).length)
	    return str;
	else
	    return String(str).substring(0,n);
}

function Right(str, n){
    if (n <= 0)
       return "";
    else if (n > String(str).length)
       return str;
    else {
       var iLen = String(str).length;
       return String(str).substring(iLen, iLen - n);
    }
}


function Mostra(x)
{
  if (document.getElementById(x)) 
	  document.getElementById(x).style.display = '';
}


function Nascondi(x)
{
  if (document.getElementById(x)) 
    document.getElementById(x).style.display = 'none';
}


function MostraNascondi(x)
{
  if (document.getElementById(x)) 
  {
    if (document.getElementById(x).style.display == '')
    {
    	document.getElementById(x).style.display = 'none';
    }
    else
    {
    	document.getElementById(x).style.display = '';
    }
  }
}

var isNS4 = (document.layers) ? true : false;
var isIE4 = (document.all && !document.getElementById) ? true : false;
var isIE5 = (document.all && document.getElementById) ? true : false;
var isNS6 = (!document.all && document.getElementById) ? true : false;

function switchDiv(strDivName,bolVisible)
{
	if (isNS4)
	{
	 objElement = document.layers[strDivName];
	}
	else if (isIE4)
	{
	 objElement = document.all[strDivName];
	}
	else if (isIE5 || isNS6)
	{
	 objElement = document.getElementById(strDivName);
	}
	
	if(isNS4){
	   if(!bolVisible) {
		 objElement.visibility ="hidden"
	   } else {
		 objElement.visibility ="visible"
	   }     
	 }else{
	   if(!bolVisible) {
		 objElement.style.visibility = "hidden";
	   } else {
		 objElement.style.visibility = "visible";
	   }
	}
}