聊天自动滚动到底部

<div class="chat" id="scrollDiv"></div>
vue2
this.$nextTick(() => {
   var scrolltop = document.getElementById("scrollDiv");
   scrolltop.scrollTop = scrolltop.scrollHeight;
});

vue3
import { nextTick } from "vue";
var scrolltop = document.getElementById("scrollDiv");
nextTick(() => {
　　if (scrolltop != null) {
      scrolltop.scrollTop = scrolltop.scrollHeight;
　　}
});