Vue3 Watch监听函数

tep1：引入watch函数和toRaw方法

import { watch, toRaw } from "vue"

tep2:监听

// 监听函数，监听formState对象,对象类型监听要开启deep深度监听
watch(
  formState,
  (newData, oldData) => {
    console.log(toRaw(newData), toRaw(oldData));//toRaw()为取到proxy对象中的数据
  },
  {
    deep: true,
  }
);

tep3:监听对象中某一属性的变化时需要改为回调函数

watch(
  () => formState.value.user,
  () => console.log(formState.value.user)
);