el-date-picker 限制30天

      <el-date-picker
              v-model="dateRange"
              size="small"
              style="width: 240px"
              value-format="yyyy-MM-dd"
              type="daterange"
              range-separator="-"
              start-placeholder="开始日期"
              end-placeholder="结束日期"
              :picker-options="pickerOptions"
            ></el-date-picker>

      pickerOptions: {
        onPick: ({ maxDate, minDate }) => {
          this.selectDate = minDate.getTime()
          if (maxDate) {
            this.selectDate = ''
          }
        },
        disabledDate: (time) => {
          if (this.selectDate !== '') {
            const one = 30 * 24 * 3600 * 1000
            const minTime = this.selectDate - one
            const maxTime = this.selectDate + one
            return time.getTime() < minTime || time.getTime() > maxTime
          }
        }

      },