element-ui和vue表单(对话框)验证提示语(残留)清除操作

  let result = Vue.extend({
   name: 'recommend-list',
   template: template,
   watch: {
    dialogSequenceVisible: function (val,oldVla) {
     this.$refs["form"].resetFields();
    }
   },
   data() {
    let validateSequence = (rule, value, callback) => {
     let val = this.trim(value);
     if (val == '') {
      callback(new Error('顺序值不允许为空'));
     } else if (value > 9223372036854775807) {
      callback(new Error('顺序值不能超过9223372036854775807'));
     } else if (!this.isNumber(val)) {
      callback(new Error('必须输入正整数'));

<el-dialog title="调整顺序" :visible.sync="dialogSequenceVisible" style="width:80%" @close='closeDialog'>
 
   <el-form label-width="200px" :model="form" style="margin:0 auto;" :rules="rules" ref="form">
 
    <el-form-item label="请输入调整的顺序值："
        prop="sequence">
     <el-input v-model="form.sequence" style="width:200px" auto-complete="off"></el-input>
    </el-form-item>
 
   </el-form>
   <div slot="footer" class="dialog-footer">
    <el-button @click="dialogSequenceVisible = false">取 消</el-button>
    <el-button type="primary" @click="position()">确 定</el-button>
   </div>
  </el-dialog>

  let result = Vue.extend({
   name: 'recommend-list',
   template: template,
   watch: {
    dialogSequenceVisible: function (val,oldVla) {
     if (this.$refs['form'] != undefined) {
      this.$refs["form"].resetFields();
     }
    }
   },