使用Element+vue实现开始与结束时间限制

<el-form-item label="开始时间">   <el-date-picker v-model="startDate" type="datetime" placeholder="选择日期"                   format="yyyy-MM-dd HH:mm:ss"                   value-format="timestamp"                   :editable="false"                   :picker-options="pickerOptionsStart" @change="changeStart">   </el-date-picker></el-form-item><el-form-item label="结束时间">   <el-date-picker v-model="endDate" type="datetime" placeholder="选择日期"                   style="width: 100%;"                   format="yyyy-MM-dd HH:mm:ss"                   value-format="timestamp"                   :clearable="true"                   :editable="false"                   :picker-options="pickerOptionsEnd" @change="changeEnd">   </el-date-picker></el-form-item>

pickerOptionsStart: {},pickerOptionsEnd: {},startDate: '',endDate: '', changeStart() { // 限制开始时间        if (this.endDate != '') {          if (this.endDate <= this.startDate) {            this.$message.warning('结束时间必须大于开始时间！');            this.startDate = '';          }        }        this.pickerOptionsEnd = Object.assign({}, this.pickerOptionsEnd, {          disabledDate: (time) => {            if (this.startDate) {              return time.getTime() < this.startDate;            }          },        });      },      changeEnd() { // 限制结束时间        console.log(this.endDate);        if (this.startDate != '') {          if (this.endDate <= this.startDate) {            this.$message.warning('结束时间必须大于开始时间！');            this.endDate = '';          }        }        this.pickerOptionsStart = Object.assign({}, this.pickerOptionsStart, {          disabledDate: (time) => {            if (this.endDate) {              return time.getTime() > this.endDate;            }          },        });      },