Vue环境下，点击按钮进行上下页的切换

<template>
  <div id="page">
    <button class="btn" @click="prePage()">上一页</button>
    <ul>
      <li :class="selected == index ?'page1':'page'" v-for="(item,index) of pageCount" :key="index">{{item}}</li>
    </ul>
    <button class="btn" @click="nextPage()">下一页</button>
  </div>
</template>
<script>
  export default {
    data() {
      return {
        pageCount: 10, //总页数
        selected: 0 //已选择的页，默认开始时为第一页
        //因为是与下标index作比较，所以要从0开始；0代表第一页，依次类推
      }
    },
    methods: {
      //上一页
      prePage() {
        //如果已经在第一页，点击按钮页码不变并弹出提示
        if (this.selected == 0) {
          this.selected;
          alert('已经是第一页！');
          //否则当前页数-1
        } else {
          this.selected = this.selected - 1;
        }
      },
      //下一页
      nextPage() {
        //如果已经在最后一页，点击按钮页码不变并弹出提示
        if (this.selected == this.pageCount - 1) {
          this.selected;
          alert('已是最后一页！');
        } else {
          //否则当前页数+1
          this.selected = this.selected + 1;
        }
      }
    }
  }
</script>
<style scoped lang="less">
  * {
    font-size: 14px;
    font-weight: normal;
  }
  #page {
    display: flex;
    width: 80%;
    margin: auto;
    .btn {
      width: 70px;
      height: 35px;
      color: white;
      font-weight: bold;
      border: 0;
      margin: 0 5px;
    }
    .btn:hover {
      cursor: pointer;
    }
    .btn:active {
      background-color: #787878;
    }
  }
  ul {
    list-style: none;
    /*未选中时的页码样式*/
    li, .page {
      float: left;
      width: 35px;
      height: 35px;
      text-align: center;
      line-height: 35px;
      border: 1px solid lightskyblue;
      color: lightskyblue;
      margin: 0 3px;
    }
    /*选中后的页码样式*/
    .page1 {
      background-color: lightskyblue;
      color: white;
    }
  }
</style>