vue3 内容过多出现滚动条时滚动条自动定位到末端的操作代码

<div class="top" ref="tagRef">
    <el-tag
        type="ghost"
        size="large"
        v-for="tag in selectTag"
        :key="tag.id"
        :closable="true"
        style="padding-left: 8px; padding-right: 8px"
        @close="() => handleClose(tag)"
    >
        {{
              tag.show ||
              (Array.isArray(tag.prompt)
                ? tag.prompt.join(',')
                : tag.prompt)
            }}
          </el-tag>
        </div>
const tagRef = ref();
watch(selectTag.value, async() => {
  await nextTick();
  const topElement = tagRef.value;
  if(topElement) {
    topElement.scrollTop = topElement.scrollHeight;
  }
});

  function scrollTop() {
    if (leftRef.value) {
      console.log('99', leftRef.value);
      nextTick(() => {
        leftRef.value.scrollTop = 1000;
        // scrollBy(0, document.body.scrollWidth);
      });
    }
  }
onMounted(async () => {
    if (router.currentRoute.value.query.id) {
      positionChooseCode.value = router.currentRoute.value.query.id;
      positionStatusValue.value = router.currentRoute.value.query.id;
    }
    const positionId = router.currentRoute.value.query.positionId;
    if (!!positionId) {
      cStore.setPositionId(positionId);
    }
    console.log('mounted--positionId', positionId);
    await getPositionDictionary(positionChooseCode.value, '');
    await getDictionaries();
    scrollTop();
  });

    console.log('positionList.value', positionList.value);
    rowItemId.value = item.id;
    //找到前面有多少个元素
    let index = positionList.value.findIndex((it) => it.id === rowItemId.value);
    console.log('找到前面有多少个元素', index + 1);
    num.value = index - 2;
获取当前职位，当前职位会有class==red的，通过class获取ele;
 const sortableEles = document.querySelectorAll('.red');
      console.log(sortableEles);
      let itemHeight = 0;
      if (sortableEles.length > 0) {
        const firstListItem = sortableEles[0];
        itemHeight = firstListItem.offsetHeight; // 获取元素的高度，包括内边距和边框
        console.log('第一个列表项的高度:', itemHeight);
        console.log(' num.value', num.value);
      }