方法一  getElementById or something else

<div class="book-navbar-menutree" id="menuTree" name="menuTree">

onMounted(() => { var menu = document.getElementById('menuTree') as HTMLElementmenu.innerHTML = menuTreeStr.value
})

方法二 getCurrentInstance 

import { getCurrentInstance } from "vue"

onMounted(() => { (getCurrentInstance()?.refs.menuTree as HTMLElement).innerHTML = menuTreeStr.value
})或者const instance = getCurrentInstance();(instance?.refs.menuTree as HTMLElement).innerHTML = menuTreeStr.value

 

方法三 ref

const menuTree = ref<HTMLElement>()

<div class="book-navbar-menutree" ref="menuTree">

onMounted(() => { menuTree.value?.innerHTML
})