//check str is a empty string or not
function isEmpty(str)
{
	if (str=="") return true;
	var pattern=/^\s+$/;
	var result=str.match(pattern);
	if (result!=null) return true;
	return false;
}

//check str is format("yyyy-mm") or not
function isYearMonth(str)
{
	if (isEmpty(str)) return false;
	var pattern=/^[0-9]{4}-(0[1-9]{1}|1[0-2]{1})$/;
	var result=str.match(pattern);
	if (result!=null) return true;
	return false;
}

//check str is date-format("yyyy-mm-dd") or not
function isDate(str)
{
	if (isEmpty(str)) return false;
	var pattern=/^[0-9]{4}-(0[0-9]{1}|1[0-2]{1})-(0[1-9]{1}|[1-2]{1}[0-9]{1}|3[0-1]{1})$/;
	var result=str.match(pattern);
	if (result!=null) return true;
	return false;
}

//check str is a integer or not
function isInteger(str)
{
	if (isEmpty(str)) return false;
	var pattern=/^-?[0-9]+$/;
	var result=str.match(pattern);
	if (result!=null) return true;
	return false;
}

//check str is decimal or not
function isDecimal(str)
{
	if (isEmpty(str)) return false;
	var pattern=/^-{0,1}[0-9]{1,}.[0-9]{1,}$/;
	var result=str.match(pattern);
	if (result!=null) return true;
	return false;
}

//check str is integer or decimal
function isNumber(str)
{
	if (isEmpty(str)) return false;
	if (isInteger(str)) return true;
	if (isDecimal(str)) return true;
	return false;
}

//check whether str contains chinese character or not
function hasChinese(str)
{
	var pattern=/[\u4e00-\u9fa5]+/;
	var result=str.match(pattern);
	if (result!=null) return true;
	return false;
}