vue报错信息（Avoid using non-primitive value as key, use stringnumber value instead.）

避免使用非原始值作为关键字，而使用字符串/数字值代替。
解决方法：

<el-carousel class="swiper-container" :interval="5000" arrow="hover" @change="carouselItem">
  <el-carousel-item v-for="item in photoList" :key="item">
    <div class="swiper-slide">
      <div class="swiper" v-for="index in item">
       <a @click='goTo(2)' ><img  :src="index" /></a>
      </div>
    </div>
  </el-carousel-item>
</el-carousel>

for循环中，绑定的key值不能为对象，而是取一个字符串或数值，如下图：

<el-carousel class="swiper-container" :interval="5000" arrow="hover" @change="carouselItem">
  <el-carousel-item v-for="item in photoList" :key="item.id">
    <div class="swiper-slide">
      <div class="swiper" v-for="index in item">
       <a @click='goTo(2)' ><img  :src="index" /></a>
      </div>
    </div>
  </el-carousel-item>
</el-carousel>