elementui el-select change事件传参问题

   <el-select v-model="ruleForm.userName" :loading="commissionerListLoading" value-key="item" class="control" placeholder="请选择" @change="handleCommissioer">
            <el-option v-for="(item,idx) of commissionerList" :key="idx" :label="item.userName" :value="item"/>
          </el-select>

  // 选择专员姓名
      handleCommissioer(val) {
        console.log(val)
 
        this.ruleForm.userName = val.userName
        this.ruleForm.userCode = val.userCode
        this.getLifeInsurance(val.userCode)
      },

// An highlighted block
<el-table border stripe :data="searchForm.taxPlanEntityList" style="width: 100%">
  <el-table-column label="公司名称" align="center" min-width="140" show-overflow-tooltip>
    <template slot-scope="{row,$index}" >
      <el-select v-model="row.deptId" placeholder="请选择" @change="(deptId) => handleChangeDeptId(deptId, $index)">
         <el-option v-for="item in projectList" :label="item.name" :value="item.deptId" :key="item.deptId"></el-option>
       </el-select>
     </template>
   </el-table-column>
 </el-table>

handleChangeDeptId(deptId, index) {
   console.log(deptId, index) // 这个就是你传过来的值了
}