SOURCE

new Vue({
  el: '#app',
  data() {
    return {
      list: [1, 3, 4, 5, 6]
    }
  },
  methods: {
    del(index) {
      this.list.splice(index, 1)
    }
  }
})

<div id="app">
  <div class="test1">
    <ul>
      <li v-for="(item,index) in list" :key="index">
        <span>{{item}}</span>
        <button @click="del(index)">删除</button>
      </li>
    </ul>
  </div>
  <div class="test2">
    
  </div>
</div>