vue 回到顶部

组件

BackToTop.vue 组件模板

<template>
  <transition :name="transitionName">
    <div v-show="visible" :style="customStyle" class="back-to-ceiling" @click="backToTop">
      <!-- 注释部分可自行更改 -->
      
      <!-- <svg width="16" height="16" viewBox="0 0 17 17" xmlns="http://www.w3.org/2000/svg" class="Icon Icon--backToTopArrow" aria-hidden="true" style="height: 16px; width: 16px;">
        <title>回到顶部</title>
        <g>
          <path d="M12.036 15.59c0 .55-.453.995-.997.995H5.032c-.55 0-.997-.445-.997-.996V8.584H1.03c-1.1 0-1.36-.633-.578-1.416L7.33.29c.39-.39 1.026-.385 1.412 0l6.878 6.88c.782.78.523 1.415-.58 1.415h-3.004v7.004z" fill-rule="evenodd"/>
        </g>
      </svg> -->
      
      <!-- <div class="backTopDiv">
        <img style="width:80%;height:80%;" src="../assets/footer/top.png" alt="">
      </div> -->
    </div>
  </transition>
</template>

<script>
export default {
  name: 'BackToTop',
  props: {
    visibilityHeight: {
      type: Number,
      default: 400
    },
    backPosition: {
      type: Number,
      default: 0
    },
    customStyle: {
      type: Object,
      default: function() {
        return {
          right: '50px',
          bottom: '50px',
          width: '40px',
          height: '40px',
          'border-radius': '4px',
          'line-height': '45px',
          background: '#e7eaf1'
        }
      }
    },
    transitionName: {
      type: String,
      default: 'fade'
    }
  },
  data() {
    return {
      visible: false,
      interval: null,
      isMoving: false
    }
  },
  mounted() {
    window.addEventListener('scroll', this.handleScroll)
  },
  beforeDestroy() {
    window.removeEventListener('scroll', this.handleScroll)
    if (this.interval) {
      clearInterval(this.interval)
    }
  },
  methods: {
    handleScroll() {
      this.visible = window.pageYOffset > this.visibilityHeight
    },
    backToTop() {
      // window.scrollTo(0, 0)

      if (this.isMoving) return
      const start = window.pageYOffset
      let i = 0
      this.isMoving = true
      this.interval = setInterval(() => {
        const next = Math.floor(this.easeInOutQuad(10 * i, start, -start, 500))
        if (next <= this.backPosition) {
          window.scrollTo(0, this.backPosition)
          clearInterval(this.interval)
          this.isMoving = false
        } else {
          window.scrollTo(0, next)
        }
        i++
      }, 16.7)
    },
    easeInOutQuad(t, b, c, d) {
      if ((t /= d / 2) < 1) return c / 2 * t * t + b
      return -c / 2 * (--t * (t - 2) - 1) + b
    }
  }
}
</script>

<style scoped>
  .back-to-ceiling {
    position: fixed;
    display: inline-block;
    text-align: center;
    cursor: pointer;
  }
  .back-to-ceiling:hover {
    background: #d5dbe7;
  }
  .fade-enter-active,
  .fade-leave-active {
    transition: opacity .5s;
  }
  .fade-enter,
  .fade-leave-to {
    opacity: 0
  }
  .backTopDiv{
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
  }
</style>
           

使用示例

<template>
  <div id="app">
    <!--可自定义按钮的样式、show/hide临界点、返回的位置  -->
    <!--如需文字提示，可在外部添加element的<el-tooltip></el-tooltip>元素（例如以下）  -->
    <el-tooltip placement="top" content="回到顶部">
      <back-to-top :custom-style="myBackToTopStyle" :visibility-height="300" :back-position="0" transition-name="fade"/>
    </el-tooltip>
  </div>
</template>

<script>
import  BackToTop from '../components/BackToTop'// 引入上文那个组件 路径自己确认下
export default {
  name: 'app',
  components: { BackToTop},
  data() {
    return {
      myBackToTopStyle: {
        right: '5.5%',
        bottom: '70px',
        width: '40px',
        height: '40px',
        borderRadius: '4px',
        background: '#e7eaf1',// 按钮的背景颜色
        'border-radius': '50%'
      }
    }
  }
}
</script>