element ui datepicker 計算開始時間和結束時間的時間差

getTime(beginTime, endTime) {
      var dateDiff = endTime.getTime() - beginTime.getTime(); //時間差的毫秒數
      var dayDiff = Math.floor(dateDiff / (24 * 3600 * 1000)); //計算出相差天數
      var leave1 = dateDiff % (24 * 3600 * 1000); //計算天數后剩余的毫秒數
      var hours = Math.floor(leave1 / (3600 * 1000)); //計算出小時數
      //計算相差分鍾數
      var leave2 = leave1 % (3600 * 1000); //計算小時數后剩余的毫秒數
      var minutes = Math.floor(leave2 / (60 * 1000)); //計算相差分鍾數
      //計算相差秒數
      var leave3 = leave2 % (60 * 1000); //計算分鍾數后剩余的毫秒數
      var seconds = Math.round(leave3 / 1000);
      console.log(
        " 相差 " +
          dayDiff +
          "天 " +
          hours +
          "小時 " +
          minutes +
          " 分鍾" +
          seconds +
          " 秒"
      );
      return "相差 " + dayDiff + "天 " + hours + "小時 " + minutes + " 分鍾";
    },

開始時間和結束時間時間差

<div class="des-status-df">開始</div>
              <div class="block">
                <el-date-picker
                 
                  v-model="startTime"
                  type="datetime"
                  placeholder="選擇日期時間"
                  @change="jsTime"
                >
                </el-date-picker>
              </div>
              <div class="des-status-df">結束</div>
              <div class="block">
                <el-date-picker
                 
                  v-model="endTime"
                  type="datetime"
                  placeholder="選擇日期時間"
                  @change="jsTime"
                >
                </el-date-picker>
              </div>
              <div class="des-time-box">
                <span class="des-time">共計</span>
                <span class="des-time-red">{{duration}}</span>
                <span class="des-time">小時</span>
              </div>

data

duration: "",
startTime: "",
endTime: "",