prop里面的值和v-model中的值一一对应时，表单的校验会生效
那么动态生成的表单如何添加校验
1.修改prop值
2.给每一个表单项添加rules验证

model：
 <el-form class="pac-form" 
                     :model="goodsNameForm"
                     :rules="goodsNameFormRules"
                     ref="goodsNameFormRef">
  <div class="pac-wrap" v-for="(pItem,pIdx) in goodsNameForm.pacList" :key="pItem.goodsId">
   <el-form-item :prop="`pacList[${pIdx}].parcelLength`" :rules="goodsNameFormRules.parcelLength">
        <el-input-number :precision="1" :max="1000" :controls="false" v-model="pItem.parcelLength" size="small" clearable @change="changeVolume(pIdx)"></el-input-number>
  </el-form-item>
</div>
</el-form>

data:
 goodsNameForm: {
                pacList: [{
                   "goodsWeight":undefined,
                    "id":0,
                    "parcelHigh":undefined,
                    "parcelLength":undefined,
                    "parcelVolume":undefined,
                    "parcelWidth":undefined,
                    "isSpand":true,
                    "expressOrderGoodsList":[
                        {
                            "currencyType": "",
                            "goodsName": "",
                            "goodsQTY": undefined,
                            "goodsType": "",
                            "goodsValue": undefined,
                            "orderId": 0
                        }
                    ]
                }],
            }

computed
        'goodsNameFormRules' () {
            return {
                 parcelLength: [
                    { required: true, message: this.$t('is.null'), trigger: 'blur' }
                ],
                goodsQTY: [
                    { required: true, message: this.$t('is.null'), trigger: 'blur' }
                ]
            }
        }

参考链接
https://www.jianshu.com/p/0ff811edf9f4