Vue3处理大数据量渲染和优化的方法小结

<template>
  <div class="container" @scroll="onScroll">
    <div class="spacer" :style="{ height: spacerHeight + 'px' }"></div>
    <div class="item" v-for="(item, index) in visibleItems" :key="index">
      {{ item }}
    </div>
  </div>
</template>

<script>
export default {
  data() {
    return {
      items: Array.from({ length: 10000 }, (_, index) => `Item ${index + 1}`),
      startIndex: 0,
      endIndex: 20,
    };
  },
  computed: {
    visibleItems() {
      return this.items.slice(this.startIndex, this.endIndex);
    },
    spacerHeight() {
      return this.items.length * 20; // 每个项的高度
    },
  },
  methods: {
    onScroll(event) {
      const scrollTop = event.target.scrollTop;
      const itemHeight = 20;
      this.startIndex = Math.floor(scrollTop / itemHeight);
      this.endIndex = this.startIndex + 20;
    },
  },
};
</script>

<style scoped>
.container {
  height: 400px;
  overflow-y: scroll;
  position: relative;
}
.spacer {
  width: 100%;
}
.item {
  height: 20px;
  box-sizing: border-box;
  border-bottom: 1px solid #ccc;
}
</style>

<template>
  <div v-once>
    <p>这段内容仅会渲染一次：{{ staticContent }}</p>
  </div>
</template>

<script>
export default {
  data() {
    return {
      staticContent: '这是静态内容'
    };
  }
};
</script>

template>
  <div>
    <div v-for="(item, index) in visibleItems" :key="index">
      {{ item }}
    </div>
    <button @click="loadMore">加载更多</button>
 div>
</template>

<script>
export default {
  data() {
    {
      items: Array.from({ length: 10000 }, (_, index) => `Item ${index + 1}`),
      visibleItems: [],
      chunkSize: 100,
      currentIndex: 0,
    };
  },
  created() {
    this.loadMore();
  },
  methods: {
    loadMore() {
      if (this.currentIndex < this.items.length) {
        this.visibleItems.push(...this.items.slice(this.currentIndex, this.currentIndex + this.chunkSize));
        this.currentIndex += this.chunkSize;
      }
    },
  }
};
</script>

<template>
  <div @scroll="onScroll">
    <div class="content" :style="{ height: scrollHeight + 'px' }">
      内容...
    </div>
  </div>
</template>

<script>
export default {
  data() {
    return {
      scrollHeight: 2000,
      ticking: false,
    };
  },
  methods: {
    onScroll(event) {
      if (!this.ticking) {
        window.requestAnimationFrame(() => {
          // 处理滚动事件
          this.ticking = false;
        });
        this.ticking = true;
      }
    },
  },
};
</script>

<style scoped>
.content {
  width: 100}
</style>

<template>
  <div>
    <p>{{ computedItem }}</p>
  </div>
</template>

<script>
export default {
  data() {
    return {
      items: [/* 大量数据 */],
    };
  },
  computed: {
    computedItem() {
      return this.items.map(item => {
        // 简化计算逻辑
        return `Item: ${item.name}`;
      });
    },
  },
};
</script>