function GetRadioButtonValue(RadioObj)
{
	for(Index = 0; Index <= RadioObj.length; Index++) {
		if(RadioObj[Index].checked == true) { return RadioObj[Index].value; }
	}
	return false;
} // END function GetRadioButtonValue(RadioObj)

function isblank(field)
{
	if(field == "") {
		return true;
	}
	for (var i=0; i < field.length; i++)
	{
		var c=field.charAt(i);
   		if ((c != ' ') && (c != '\n') && (c != '\t')) return false;
	}
	return true;
} // END function isblank(field)

function isnum(field)
{
	ok = true;
	for (var i=0; i < field.length; i++)
	{
		var c=field.charAt(i);
   		if ((c < '0') || (c > '9')) ok = false;
	}
	return ok;
} // END function isnum(field)

function isemail(field)
{
	ok = false;
	for (var i=0; i < field.length; i++)
	{
		var c=field.charAt(i);
   		if ((c == '@')) ok = true;
	}
	return ok;
} // END function isemail(field)

function IsUSphoneNumber(PhoneNumber)
{
	// check that phone number is like 
	// 777-777-7777 or (777) 777 7777, with variants for the space/dash characters
	PhonePattern = new RegExp("^[\(]?[0-9]{3}[\) -]*[0-9]{3}[ -]?[0-9]{4}.*$");
	return (PhonePattern.exec(PhoneNumber) != null); // true on match, false on no match
} // END function IsUSphoneNumber()

function IsUSzipCode(zip)
{
	// check that zip is at least 5 digits, with possible extension numbers
	ZipCodePattern = new RegExp("^([0-9]{5}[- ]{1}[0-9]{4}|[0-9]{5})$");
	return (ZipCodePattern.exec(zip) != null); // true on match, false on no match
} // END function IsUSzipCode(zip)