//
// IsAlphaNumeric
//
function IsAlphaNumeric(aValue)
{
	re = /[^a-zA-Z0-9\_]/;
	iSearch = re.exec(aValue);
	if (iSearch == null)
		return true;
	return false;
		
}

//
// isNumeric
//
function isNumeric(aValue, iNullAllowed)
{
	//get length of string
	iLength = aValue.length;
	//check if null
	if (iLength == 0 && iNullAllowed == 1)
		return true;
	re = /^[0-9]+.?[0-9]*$/;
	iSearch = re.exec(aValue);
	if (iSearch == null)
		return false;
	return true;
		
}

//
// isEmail
//
function isEmail(aValue, iNullAllowed)
{
	//get length of string
	iLength = aValue.length;
	//check if null
	if (iLength == 0 && iNullAllowed == 1)
		return true;
	re = /^[a-zA-Z0-9_.\-]+\@[a-zA-Z0-9_.\-]+\.[a-zA-Z0-9_\-]+$/;
	iSearch = re.exec(aValue);
	if (iSearch == null)
		return false;
	return true;
		
}

//
// isLogin
//
function isLogin(aValue, iNullAllowed)
{
	//get length of string
	iLength = aValue.length;
	//check if null
	if (iLength == 0 && iNullAllowed == 1)
		return true;
	re = /^[a-zA-Z0-9_.\-]+$/;
	iSearch = re.exec(aValue);
	if (iSearch == null)
		return false;
	return true;
		
}

//
// isHttp
//
function isHTTP(aValue, iNullAllowed)
{
	//get length of string
	iLength = aValue.length;
	//check if null
	if (iLength == 0 && iNullAllowed == 1)
		return true;
	re = /^http:\/\/[a-zA-Z0-9_\-]+\.[a-zA-Z0-9_\-]+\.[a-zA-Z0-9_\-]+/;
	iSearch = re.exec(aValue);
	if (iSearch == null)
		return false;
	return true;
}

//
// isDate
//
function isDate(aValue, iNullAllowed)
{
	//get length of string
	iLength = aValue.length;
	//check if null
	if (iLength == 0 && iNullAllowed == 1)
		return true;
	re = /^(\d{2})-(\d{2})-(\d{4})$/;
	iSearch = re.exec(aValue);
	if (iSearch == null)
		return false;
	else
	{
		iDay 	= RegExp.$1
		iMonth 	= RegExp.$2
		iYear 	= RegExp.$3
		if (iDay <= 0 || iDay > 31)
			return false;
		if (iMonth <= 0 || iMonth > 12)
			return false;
		if (iYear < 1900 || iYear > 2100)
			return false;
	}
	return true;
}


//
// isString
//
function isString(aValue, iSizeMin, iSizeMax, iNullAllowed)
{
	//get length of string
	iLength = aValue.length;
	//check if null
	if (iLength == 0 && iNullAllowed == 1)
		return true;
	if ( iLength < iSizeMin || iLength > iSizeMax)
		return false;
	return true;
}