轉(zhuǎn)載一文章
https://blog.csdn.net/weixin_43845137/article/details/123534181
1,父組件
<template>
   <div>
    <Child 
    v-model:custom="message"
    @update:custom="updateCustom"
    ></Child>
    <h1>父急？{{ message }}</h1>
  </div>
</template>
<script lang="ts" setup>
import { ref, unref } from 'vue';
import Child from './testCom.vue';
let message = ref("Hello World Vue3");
const updateCustom = (val) => {
  message.value = val
}

</script>
1,子組件
<template>
  <div> <input v-model="propsMessage" type="text"> </div>
</template>

<script setup lang="ts">
import { ref, computed } from "vue";
let props = defineProps({
  custom: String
})
const emmits = defineEmits(['update:modelValue', 'update:custom'])
const propsMessage = computed({
  get: () => {
    return props.custom
  },
  set: (val) => {
    console.log("sssssss")
    emmits('update:custom', val)
  }
})

</script>
<style scoped>
.footer-wrap {
  display: flex;
  justify-content: flex-end;
}
</style>

2,實(shí)例
//父組件
<template>
   <div>
    <Child v-model="showAdress" ></Child>
    <button @click="open">展示</button>    
  </div>
</template>
<script lang="ts" setup>
import { ref, unref } from 'vue';
import Child from './testCom.vue';
const showAdress = ref(false)
function open() {
  showAdress.value = true
}

</script>

//子組件
<script setup>
// props
const props = defineProps({
  'model-value': {
    type: Boolean,
    required: false,
    default: false
  }
});
const emit = defineEmits(['update:model-value']);
function close() {
  emit('update:model-value', false)
}
</script>
<template>
  <div v-if="modelValue">
    <div class="">我是子組件</div>
    <button @click="close">關(guān)閉</button>    
  </div>
</template>

代碼塊

**************************************************************************
3.支持多個(gè)
//父組件

<template>
   <div>
    <Child v-model="flag"  v-model:title="title" ></Child>
    <button  @click="flag = !flag">展示</button>    
  </div>
</template>

<script lang="ts" setup>
import { ref, unref } from 'vue';
import Child from './testCom.vue';
let flag = ref<Boolean>(true)
  let title = ref<String>('我是小渣亮')
const showAdress = ref(false)
function open() {
  showAdress.value = true
}

</script>
//子組件

<template>
  <div v-if="modelValue" class="dialog">
    <div class="dialog-header">
      <span>標(biāo)題 - {{ title }}</span>
      <button @click="close">關(guān)閉</button>
    </div>
    <div class="dialog-main">
      <button @click="changTitle">修改 標(biāo)題</button>
      {{ modelValue }}
    </div>
  </div>
</template>
<script setup lang="ts">
type Props = {
  modelValue: Boolean
  title: String
}
defineProps<Props>()

const emit = defineEmits(['update:modelValue', 'update:title'])
const close = () => {
  emit('update:modelValue', false)
}
const changTitle = () => {
  emit('update:title', '我就是狗啊')
}
</script>
<script lang="ts">
export default {
  name: 'Dialog',
}
</script>