function isEmpty(stringa) { 

	return ((stringa == null) || (stringa.length == 0));

}



function IsEmail(stringa){

	var dataExp = /^[a-z0-9_-]+(\.[a-z0-9_-]+)*@[a-z0-9_-]+(\.[a-z0-9_-]+)+$/;

	return dataExp.test(stringa);

}



function IsProv(stringa){

	var dataExp = /^[a-zA-Z]{2}$/;

	return dataExp.test(stringa);

}



//Funzione che conta i checkbox selezionati nel form

function CountChecked(Nome_Form,Nome_Check)

 {

	form = eval("document.forms['" + Nome_Form + "']");

	count = 0;



	for (i=0 ; i < form.length ; i++) {

		if (form.elements[i].name == Nome_Check) {

			if (form.elements[i].checked) {

				count++;

			}

		}

	}



	return(count);

}



function SelectParametroNonValido(Form_Select, Msg, Value) {

	var retVal = true;

	var formSelect = eval(Form_Select);

	var optionId = formSelect.selectedIndex;

	

	if (formSelect.options[optionId].value == Value) {

		alert(Msg);

		retVal = false;

	}

	

	return retVal;

}



function isDate (year, month, day) {

	// catch invalid days, except for February

	year = parseInt(year);

	month = parseInt(month);

	day = parseInt(day);



	if (day > daysInMonth[month-1]) return false; 

	if ((month == 2) && (day > daysInFebruary(year))) return false;

	return true;

}



function daysInFebruary (year) {

	// February has 29 days in any year evenly divisible by four,

	// EXCEPT for centurial years which are not also divisible by 400.

	return (  ((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0) ) ) ? 29 : 28 );

}



// must programmatically check Ferbruary

var daysInMonth = new Array(31,29,31,30,31,30,31,31,30,31,30,31);





function IsNumber(str) {

	var numberExp = /^\+[0-9]{1,}$/;

	return(numberExp.test(str));

}



function IsCap(str) {

	var numberExp = /^[0-9]{5}$/;

	return(numberExp.test(str));

}



function IsEuro(cifra){

	var dataExp = /^[0-9]+\.[0-9]{2}$/;

	return dataExp.test(cifra);

}



function ContaCaratteri(Tree_Modulo, nomenometextarea, maxlength){

	

	var msgLen;

	var textareaform;

		textareaform = eval(Tree_Modulo + "." + nomenometextarea);

		msgLen = textareaform.value.length;

	

		if (msgLen >= maxlength ){

			textareaform.value = textareaform.value.substr(0, maxlength);

		}

}





function IsPhone(str) {

	var numberExp1 = /^[0-9]{5,10}$/;

	var numberExp2 = /^\+[0-9]{11,13}$/;

	var numberExp3 = /^[0-9]{9,15}$/;

	var retVal = false;

	if ((numberExp1.test(str)) || (numberExp2.test(str))) {

		retVal = true;

	}

	if(str.substr(0,2) == '00') {

			retVal = false;

		if(numberExp3.test(str)) {

			retVal = true;

		}

	}

	return retVal;

}