Vue3 使用 script-setup 语法糖

可以参照这一篇看看

以下是我自己写了一个练练手，玩一玩

下面创建了一个单文件组件Button.vue,接着在App.vue中引入这个组件

Button.vue

<template>
    <div>
       <el-button @click="done">自定义按钮</el-button>
    </div>
</template>
<script setup>
import { defineProps,defineEmits } from "vue";
const props = defineProps({
  msg: String,});
const emit = defineEmits(["click"]);
function done() {
  emit("callback","传给父组件:" + props['msg']);
}
</script>

App.vue

<template>
  <el-row>
    <el-button circle><el-icon><Search/></el-icon></el-button>
  </el-row>
  {{text}}
  <My-Button :msg="text" @callback="myclick"/>
</template>
<script setup>
import { Search } from '@element-plus/icons'
import { onMounted } from '@vue/runtime-core'
import MyButton from "./components/Button"
onMounted(() =>{
    console.log('666666')
})
const text = '变量'
function myclick(msg) {
   console.log(msg)
}
</script>

效果如下

 点击“自定义按钮”，父组件传入子组件值，子组件再通过自定义事件回调将值传回父组件