vue——排他 初始化條數

<div v-for="(item,index) in arrFilter" :class="{'check':checkIndex===index}" @click="checkIndex=index">
	{{item}}
</div>

<div @click="more"></div>

export default {
    data: () => {
      return {
      	// 排他默認第 0 個元素
        checkIndex: 0,
        // 默認限制 arr 條數爲 3
        limit: 3,
        arr: []
      }
    },
    computed: {
      // 限制顯示 arr 爲 limit 值
      arrFilter: function () {
        return this.arr.slice(0, this.limit)
      },
    },
    methods: {
   	  // 展開或收起 arr
      more: function () {
        if (this.arr === 3) {
          this.limit = this.arr.length
        } else {
          this.limit = 3
        }
      }
    }
  }