vue問題五：element ui組件的開始時間-結束時間驗證

<el-date-picker  v-model="seach.before" type="date" placeholder="開始時間"  value-format="yyyy-MM-dd" class="wida" :picker-options="pickerBeginDateBefore"  @change="changeTime">
</el-date-picker>
    <span class="zhi">至</span>
<el-date-picker   v-model="seach.after" type="date" placeholder="結束時間"value-format="yyyy-MM-dd" class="wida" :picker-options="pickerBeginDateAfter">
</el-date-picker>

seach:{
  before:'',
  after:'',
},
  // 開始時間不大於結束時間
        // 開始時間
        pickerBeginDateBefore: {
          disabledDate: (time) => {
            let beginDateVal = this.seach.after;
            if (beginDateVal) {
              return time.getTime() > beginDateVal;
            }
          }
        },
        // 結束時間
        pickerBeginDateAfter: {
          disabledDate: (time) => {
            let beginDateVal = this.seach.before;
            if (beginDateVal) {
              return time.getTime() < beginDateVal;
            }
          }
        },

//選擇開始時間，清空結束時間
      changeTime(date){
        // this.seach.before="";
        // console.log(this.seach.before)
        this.pickerBeginDateAfter={
          disabledDate(time) {  //開始時間-結束時間
            return (time.getTime() < new Date(date).getTime());
          }
        }
      },