1、js 获取当前日期星期几
getWeek(time) {
  let weekDay = ["周日","周一", "周二", "周三", "周四", "周五", "周六"];    
  let myDate = new Date(Date.parse(time));  
  return weekDay[myDate.getDay()]
},
console.log(getWeek('2019-09-11')   // 周三
2、iveiw 时间限制今天之前不可选
<Date-picker 
  type="date" 
  :options="pickerOptionsStart" 
></Date-picker>
pickerOptionsStart: {
  disabledDate (time) {
    return time.getTime() < new Date(new Date().toLocaleDateString()).getTime();
  }
}
3、js 计算某个时间 前 15天 后15天
function GetDateStr(AddDayCount, date, type) { 
  var dd = new Date(date);
  dd.setDate(dd.getDate()+AddDayCount);
  var y = dd.getFullYear(); 
  var m = (dd.getMonth()+1)<10?"0"+(dd.getMonth()+1):(dd.getMonth()+1);
  var d = dd.getDate()<10?"0"+dd.getDate():dd.getDate();
  if(type){
    if(date === this.oldTime) {
      return '今天'
    } else {
      return d
    }
  } else {
    return y + "-" + m + "-" + d; 
  }
}
GetDateStr(-14, '2019-09-12')  //  2019-08-29 
GetDateStr(14, '2019-09-12')  //  2019-09-26