vue中怎么根据当前日期，推算出后面的7天日期

formatDate(start, end){

            let weekday=["周日","周一","周二","周三","周四","周五","周六"];

            let s  = this.$moment(start);

            let e  = this.$moment(end);

            //起始时间差 天数

            let diff = this.$moment(end).diff(this.$moment(start))/1000/60/60/24 ;

            //最低显示7天为了美观

            diff = diff > 7 ? diff : 7;

            //日期列表

            let listDay= [];

            // 全天

            for(let i = 0; diff > i; i++){

                let li = {

                    day:this.$moment(s).add(i, 'day').format('MM-DD'),

                    _day:this.$moment(s).add(i, 'day').format('YYYY-MM-DD'),

                    week:weekday[this.$moment(s).add(i, 'day').day()],

                    hasDocAndNum: false

                }

                listDay.push(li);

            }

        },