var nextMonthDayOne =new Date(current.getFullYear()，nextMonth，1)。var minusDate=1000*60*60*24。return new Date(nextMonthDayOne.getTime()-minusDate)；}function getCurrentMonthLastDay(){ var current=new Date()；var currentMonth=current.getMonth()；var nextMonth=++currentMonth。var nextMonthDayOne =new Date(current.getFullYear()，nextMonth，1)。