useVModel.js

import { computed } from "vue";

export default function useVModle(props, propName, emit) {
    return computed({
        get() {
            return new Proxy(props[propName], {
                get(target, key) {
                    return Reflect.get(target, key)
                },
                set(target, key, newValue) {
                    emit('update:' + propName, {
                        ...target,
                        [key]: newValue
                    })
                    return true
                }
            })
        },
        set(value) {
            emit('update:' + propName, value)
        }
    })
}

组件使用

<!-- 父组件 -->
<template>
  <div>
    <my-component v-model="form"></my-component>
  </div>
</template>
<script setup>
import myComponent from "./components/MyComponent.vue";

const form = ref({
  name: "张三",
  age: 18,
  sex: "man",
});

watch(form, (newValue) => {
  console.log(newValue);
});
</script>


<!-- 子组件 -->
<template>
  <div>
    <el-input v-model="form.name"></el-input>
    <el-input v-model="form.age"></el-input>
    <el-input v-model="form.sex"></el-input>
  </div>
</template>
<script setup>
import useVModel from "../hooks/useVModel";

const props = defineProps({
  modelValue: {
    type: Object,
    default: () => {},
  },
});

const emit = defineEmits(["update:modelValue"]);

const form = useVModel(props, "modelValue", emit);

</script>

参考原文：https://juejin.cn/post/7277089907974422588