获取本月最后一天

// 获取本月最后一天
    CurrentMonthLast(){
        var date=new Date();
        var currentMonth=date.getMonth();
        var nextMonth=++currentMonth;
        var nextMonthFirstDay=new Date(date.getFullYear(),nextMonth,1);
        var oneDay=1000*60*60*24;
        return this.formatDate(new Date(nextMonthFirstDay-oneDay));
    }