JS验证日期 比较日期

function doDateCompare(strDate){

	var ereg = /^(\d{1,4})(-|\/)(\d{1,2})(-|\/)(\d{1,2})$/;
	var checkResult = strDate.match(ereg);
	if (checkResult == null) {
		return false;
	}
	
	var year = strDate.substring(0,4);
	var month = strDate.substring(5,7);
	var day = strDate.substring(8,10);
	var currentDay = new Date(year, month -1, day);
	var checkDay  = currentDay.format("yyyyMMdd");
	if(currentDay.getFullYear() == year && (currentDay.getMonth()+1) == month && currentDay.getDate() == day){
		var nowDay = new Date().format("yyyyMMdd");
		if(checkDay <= nowDay ){
			return "Before";
		}else{
			return "After";
		}
	}else{
		return false;
	}
  
}