select下拉框change传递多个属性

1.常规select option操作

<el-select v-model="query.param.location" style="width:180px" 
        placeholder="please select" @change="changeCountry($event)">
         <el-option
           v-for="item in locations"
          :key="item.id"
          :label="item.location"
          :value="item.location">
  </el-option>
</el-select>

//js
changeCountry(value){
   //此时的value为数组中的每个对象的一个属性location
}

2.change事件传递选中多个属性到js

<el-select v-model="query.param.location" style="width:180px" 
        placeholder="please select" value-key="id" 
        @change="changeCountry($event)">
        <el-option
            v-for="item in locations"
            :key="item.id"
            :label="item.location"
            :value="item">
        </el-option>
</el-select>

//js
changeCountry(value){
   //此时的value为选中数组的整个对象
}

修改地方：
1.<el-select中增加固定写法value-key="id"
2.<el-option中的:value改为item