//Check for white space
function isBlank(s)  {
	for (var i = 0; i < s.length; i++)  {
		var c = s.charAt(i);
		if ((c != " ") && (c != "\n") && (c != "\t"))  {
			return false;
		}
	}
	return true;
}

//check for valid number
function isNumber(s)  {
	if (isNaN(s))  {		
		return false;
	}				
	return true;
}

//check for zipcode
function isZip(s)  {
	for (var i = 0; i < s.length; i++)  {
		var c = s.charAt(i);
		if ((c != "-") && (isNaN(c)))  {
			return false;
		}
	}
	return true;
}

//determine if checkbox/radio button is checked
function isChecked(s) {
  for (i=0; i<s.length; i++) {
    if (s[i].checked) {
      return true;
    }
  }
  return false;
}

//check for valid date
function isValidDate(dateStr) {
	var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{2}|\d{4})$/;
	// To require a 4 digit year entry, use this line instead:
	//var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{4})$/;
	var matchArray = dateStr.match(datePat); // is the format ok?
	if (matchArray == null) {
	//alert("Date is not in a valid format.")
	return false;
	}
	month = matchArray[1]; // parse date into variables
	day = matchArray[3];
	year = matchArray[4];
	if (month < 1 || month > 12) { // check month range
	//alert("Month must be between 1 and 12.");
	return false;
	}
	if (day < 1 || day > 31) {
	//alert("Day must be between 1 and 31.");
	return false;
	}
	if ((month==4 || month==6 || month==9 || month==11) && day==31) {
	//alert("Month "+month+" doesn't have 31 days!")
	return false
	}
	if (month == 2) { // check for february 29th
	var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
	if (day>29 || (day==29 && !isleap)) {
	//alert("February " + year + " doesn't have " + day + " days!");
	return false;
	}
	}
	return true; // date is valid
}


//check phone for 222-333-4444 format
function phoneFormat(s)  {
	for (var i = 0; i < s.length; i++)  {
		var c = s.charAt(i);
		if ((i == 0 || i == 1 || i == 2 || i == 4 || i == 5 || i == 6 || i == 8 || i == 9 || i == 10 || i == 11) && (i < 12))  {
			if (isNaN(c))  {
				return false;
			}
		}
		else if ((i == 3 || i || 7) && (i < 12))  {
			if (c != "-")  {
				return false;
			}
		}
	}
	return true;
}