微信小程序 JavaScript 指定时间加一天函数 JS 指定日期加减指定天数

dateAdd:function (startDate,days) {
  startDate = new Date(startDate);
  startDate = +startDate + days * 1000 * 60 * 60 * 24;
  startDate = new Date(startDate);
  var nextStartDate = startDate.getFullYear() + "-" + (startDate.getMonth() + 1) + "-" + startDate.getDate();
  return nextStartDate;
},