1.--ref属性

 1.1代码

1.1.1子表

<template><div class="person"><h1>中国</h1><h2 ref="title2">北京</h2><h3>尚硅谷</h3><button @click="showLog">点我输出h2这个元素</button></div>
</template><script lang="ts" setup name="Person">import {ref,defineExpose} from 'vue'// 创建一个title2，用于存储ref标记的内容let title2 = ref()let a = ref(0)let b = ref(1)let c = ref(2)function showLog(){console.log(title2.value)}defineExpose({a,b,c})
</script><style scoped>.person {background-color: skyblue;box-shadow: 0 0 10px;border-radius: 10px;padding: 20px;}button {margin: 0 5px;}li {font-size: 20px;}
</style>

1.1.2父表

<template><h2 ref="title2">你好</h2><button @click="showLog">测试</button><Person ref="ren"/>
</template><script lang="ts" setup name="App">import Person from './components/Person.vue'import {ref} from 'vue'let title2 = ref()let ren = ref()function showLog(){// console.log(title2.value)console.log(ren.value)}
</script>

 2.简单回顾TS

1.子

<template><div class="person">???</div>
</template><script lang="ts" setup name="Person">import {type PersonInter,type Persons} from '@/types'// let person:PersonInter = {id:'asyud7asfd01',name:'张三',age:60}let personList:Persons = [{id:'asyud7asfd01',name:'张三',age:60},{id:'asyud7asfd02',name:'李四',age:18},{id:'asyud7asfd03',name:'王五',age:5}]</script><style scoped>.person {background-color: skyblue;box-shadow: 0 0 10px;border-radius: 10px;padding: 20px;}button {margin: 0 5px;}li {font-size: 20px;}
</style>

<template><Person/>
</template><script lang="ts" setup name="App">import Person from './components/Person.vue'
</script>

 2.TS

export interface PersonInter {id:string,name:string,age:number
}// 一个自定义类型
// export type Persons = Array<PersonInter>
export type Persons = PersonInter[]

 3.props的使用

1.1子表

<template><div class="person"><ul><li v-for="p in list" :key="p.id">{{p.name}} -- {{p.age}}</li></ul></div>
</template><script lang="ts" setup name="Person">import {withDefaults} from 'vue'import {type Persons} from '@/types'// 只接收list// defineProps(['list'])// 接收list + 限制类型// defineProps<{list:Persons}>()//  接收list + 限制类型 + 限制必要性 + 指定默认值withDefaults(defineProps<{list?:Persons}>(),{list:()=> [{id:'ausydgyu01',name:'康师傅·王麻子·特仑苏',age:19}]})// 接收list，同时将props保存起来/* let x = defineProps(['list'])console.log(x.list) */</script><style scoped>.person {background-color: skyblue;box-shadow: 0 0 10px;border-radius: 10px;padding: 20px;}button {margin: 0 5px;}li {font-size: 20px;}
</style>

 1.2父表

<template><!-- 务必看懂下面这一行代码 --><!-- <h2 a="1+1" :b="1+1" c="x" :d="x" ref="qwe">测试</h2> --><Person a="哈哈" />
</template><script lang="ts" setup name="App">import Person from './components/Person.vue'import {reactive} from 'vue'import {type Persons} from '@/types'let x = 9let personList = reactive<Persons>([{id:'asudfysafd01',name:'张三',age:18},{id:'asudfysafd02',name:'李四',age:20},{id:'asudfysaf)d03',name:'王五',age:22}])</script>

2.TS

// 定义一个接口，用于限制person对象的具体属性
export interface PersonInter {id:string,name:string,age:number,
}// 一个自定义类型
// export type Persons = Array<PersonInter>
export type Persons = PersonInter[]

4. 对生命周期的理解

1.vue3

1. 子表

<template><div class="person"><h2>当前求和为：{{ sum }}</h2><button @click="add">点我sum+1</button></div>
</template><script lang="ts" setup name="Person">import {ref,onBeforeMount,onMounted,onBeforeUpdate,onUpdated,onBeforeUnmount,onUnmounted} from 'vue'// 数据let sum = ref(0)// 方法function add(){sum.value += 1}// 创建console.log('创建')// 挂载前onBeforeMount(()=>{// console.log('挂载前')})// 挂载完毕onMounted(()=>{console.log('子---挂载完毕')})// 更新前onBeforeUpdate(()=>{// console.log('更新前')})// 更新完毕onUpdated(()=>{// console.log('更新完毕')})// 卸载前onBeforeUnmount(()=>{// console.log('卸载前')})// 卸载完毕onUnmounted(()=>{// console.log('卸载完毕')})
</script><style scoped>.person {background-color: skyblue;box-shadow: 0 0 10px;border-radius: 10px;padding: 20px;}button {margin: 0 5px;}li {font-size: 20px;}
</style>

2.父表

<template><Person v-if="isShow"/>
</template><script lang="ts" setup name="App">import Person from './components/Person.vue'import {ref,onMounted} from 'vue'let isShow = ref(true)// 挂载完毕onMounted(()=>{console.log('父---挂载完毕')})</script>