el-form 中使用v-for创建的组件，校验规则如下：

:prop="'supplierList.' + index + '.counterParty'"

:rules="[{
            required: true,
            message: $t('required'),
            trigger: 'blur'
          }]"

以下为完整示例：

<el-form>
<template>
<el-col :xs="24" :sm="8" :md="8" :key="'counterParty'+index">
    <el-form-item :label="$t('sparePartsSupplier.counterParty')" :key="index+'counterParty'" :prop="'supplierList.' + index + '.counterParty'" :rules="[{
            required: true,
            message: $t('required'),
            trigger: 'blur'
          }]">
        <el-input v-model="item.counterParty" :placeholder="$t('sparePartsSupplier.counterParty')" />
    </el-form-item>
</el-col>
<el-col :xs="24" :sm="8" :md="8" :key="'claimantPhone'+index">
    <el-form-item :label="$t('sparePartsSupplier.claimantPhone')" :prop="'supplierList.' + index + '.claimantPhone'" :rules="[
          { required: true, message: '请输入手机号', trigger: 'blur' },
          { pattern: /^1[345789]\d{9}$/, message: '手机号码格式不正确', trigger: 'blur' }
        ]">
        <el-input :v-change-v-model='item.claimantPhoneEncrypt' v-model="item.claimantPhone" :key="'claimantPhone'+index" :placeholder="$t('sparePartsSupplier.claimantPhone')">
            <i slot="suffix" class="el-input__icon el-icon-view" title="点击查看" />
        </el-input>
    </el-form-item>
</el-col>
<el-col :xs="24" :sm="8" :md="8" :key="index+'claimantMailbox'">
    <el-form-item :label="$t('sparePartsSupplier.claimantMailbox')" :prop="'supplierList.' + index + '.claimantMailbox'" :rules="[{
            required: true,
            message: $t('required'),
            trigger: 'blur'
          }]">
        <div style="display:flex">
            <el-input :rows="1" v-model="item.claimantMailbox" :placeholder="$t('sparePartsSupplier.claimantMailbox')" type="textarea" />
        </div>
    </el-form-item>
</el-col>
</template>

</el-form>