Vue3

组合式API

1.钩子函数steup

函数的普通用法

<script>
export default {
  setup() {
    return {}
  }
}
</script>
<template>
</template>

简写使用setup

<script setup>
</script>
<template>
</template>

2.响应式API

ref函数

<script setup>
import { ref } from 'vue'
const state = ref(0)
function increment() {
  state.value++
}
</script>
<template>
  <button @click="increment">
    {{ state }}
  </button>
</template>

reactive函数

<script setup>
import { reactive } from 'vue'
const state = reactive({ count: 0 })
function increment() {
  state.count++
}
</script>
<template>
  <button @click="increment">
    {{ state.count }}
  </button>
</template>

3.计算属性API

单向响应

<script setup>
import { computed,reactive } from 'vue'
const Person=reactive({X:'张',M:'三'})
 Person.XM=computed(()=>{
  return Person.X+'-'+Person.M
 })
</script>
<template>
  姓:<input v-model="Person.X"><br>
  名:<input v-model="Person.M"><br>
  单向响应:<input v-model="Person.XM">
</template>

双向响应

<script setup>
import { computed,reactive } from 'vue'
const Person=reactive({X:'张',M:'三'})
Person.AXM=computed({
  get(){
    return Person.X+'-'+Person.M
  },
  set(value){
    const arr=value.split('-')
    Person.X=arr[0]
    Person.M=arr[1]
  }
})
</script>
<template>
  姓:<input v-model="Person.X"><br>
  名:<input v-model="Person.M"><br>
  双向响应:<input v-model="Person.AXM">
</template>

4.监听属性API

监听整个对象

<!--  // 监听整个对象,由于是浅拷贝，他们新旧指向的是通一个对象 -->
<script setup>
import {reactive,watch} from 'vue'
const Person=reactive({name:'张三',age:18, job:{salary:20}})
      watch(Person,(newVal,oldVal)=>{
         console.log('用户信息发生了变化',newVal,oldVal);
      })
</script>
<template>
 <h2>年龄：{{Person.age}}</h2>
 <button @click="Person.age++">+1</button>
</template>

监听对象中单个属性

<!-- 监听对象中单个属性,监听单个属性可以检测到新旧值 -->
<script setup>
import {reactive,watch} from 'vue'
const Person=reactive({name:'张三',age:18, job:{salary:20}})
      watch(()=>Person.age,(newVal,oldVal)=>{
         console.log('用户年龄发生了变化',newVal,oldVal);
      })
</script>
<template>
 <h2>年龄：{{Person.age}}</h2>
 <button @click="Person.age++">+1</button>
</template>

监听多个对象

<!-- 监听对象中多个个属性,监听单个属性可以检测到新旧值 -->
<script setup>
import {reactive,watch} from 'vue'
const Person=reactive({name:'张三',age:18, job:{salary:20}})
      watch([()=>Person.name,()=>Person.age],(newValue,oldValue)=>{
        console.log('person.name或者person.age的值变化了',newValue,oldValue);
      })
</script>
<template>
 <h2>姓名：{{Person.name}}</h2>
 <button @click="Person.name+='~'">修改</button>
 <h2>年龄：{{Person.age}}</h2>
 <button @click="Person.age++">+1</button>
</template>

监听对象中对象(深度监听)

<!-- 监听对象中对象,必须开启深度监听,一般情况不监听对象 -->
<script setup>
import {reactive,watch} from 'vue'
const Person=reactive({name:'张三',age:18, job:{salary:20}})
      watch(()=>Person.job,(newValue,oldValue)=>{
        console.log('person.job的值变化了',newValue,oldValue);
       },{
      deep:true
      })
</script>
<template>
 <h2>薪资：{{Person.job.salary}}K</h2>
 <button @click="Person.job.salary++">+1</button>
</template>

5.高级监听API

基本使用(默认执行一次)

<!-- watchEffect所指定的回调中用到的数据只要发生变化，则直接重新执行回调。 -->
<script setup>
import {reactive,watchEffect} from 'vue'
const Person=reactive({
        name:'张三'
      })
     watchEffect(()=>{
     Person.name
     console.log('姓名发送了变化');
     })
</script>
<template>
 <h2>姓名：{{Person.name}}</h2>
 <button @click="Person.name+='~'">修改</button>
</template>

监听御前处理oninvalidate参数

<script setup lang="ts">
import { reactive, watchEffect } from "vue";
const Person = reactive({
  name: "张三",
});
watchEffect((oninvalidate) => {
  oninvalidate(() => {
    console.log("before");
  });
  Person.name;
  console.log("姓名发送了变化");
});
</script>
<template>
  <h2>姓名：{{ Person.name }}</h2>
  <button @click="Person.name += '~'">修改</button>
</template>

停止监听

<script setup lang="ts">
import { reactive, watchEffect } from "vue";
const Person = reactive({
  name: "张三",
});
const stop = watchEffect((oninvalidate) => {
  oninvalidate(() => {
    console.log("before");
  });
  Person.name;
  console.log("姓名发送了变化");
</script>
<template>
  <h2>姓名：{{ Person.name }}</h2>
  <button @click="Person.name += '~'">修改</button>
  <button @click="stop">停止</button>
</template>

6.响应式对象解构API

toRef函数

<script setup>
import {reactive,toRef} from 'vue'
const person=reactive({A:1,B:2})
const A=toRef(person,'A')
</script>
<template>
 <h2>姓名：{{A}}</h2>
 <button @click="person.A+='~'">修改</button>
</template>

toRefs

<script setup lang="ts">
  import {reactive,toRefs} from 'vue'
  const person=reactive({A:1,B:2})
  const {A,B}=toRefs(person)
  </script>
  <template>
   <h2>姓名：{{A}}</h2>
   <button @click="A+=1">修改</button>
  </template>

7.生命周期API

<script setup>
  import {onBeforeMount,onMounted,onBeforeUpdate,onUpdated,onBeforeUnmount,onUnmounted,ref} from "vue";
  onBeforeMount(()=>{
    console.log('---挂载之前---');
   })
   onMounted(()=>{
    console.log('---挂载---');
   })
   onBeforeUpdate(()=>{
    console.log('---更新之前---');
   })
   onUpdated(()=>{
    console.log('---更新---');
   })
   onBeforeUnmount(()=>{
    console.log('---卸载之前---');
   })
   onUnmounted(()=>{
    console.log('---卸载---');
   })
</script>

8.ref获取dom

<template>
  <div>
    <div ref="box">我是div</div>
  </div>
</template>
<script>
import { ref,onMounted } from "vue";
export default {
  setup() {
    let box = ref(null); //本质是reactive({value:null})
    // 需要在生命周期获取
    onMounted(()=>{
      // 当界面挂载出来后就会自动执行
      console.log(box.value);
    })
    //接受的是null,原因是setup执行时机比mounted早,dom还没形成
    console.log(box.value);
    return { box };
  },
};
</script>

9.Hooks

(1)官方hooks

useAttrs()

<!-- 父组件 -->
<template>
  <Acom a="456" title="789" />
</template>
<!-- 子组件 -->
<!-- 获取父组件传过来的全部参数 -->
<script setup lang="ts">
import { useAttrs } from 'vue'
let attr = useAttrs()
console.log(attr)
</script>

(2)自定hooks

自定义hooks转换图片

import { onMounted } from 'vue'
type Options = {
  el: string
}
export default function (options: Options): Promise<{ baseUrl: string }> {
  return new Promise(resolve => {
    onMounted(() => {
      const img: HTMLImageElement = document.querySelector(
        options.el
      ) as HTMLImageElement
      img.onload = () => {
        resolve({
          baseUrl: base64(img)
        })
      }
    })
    const base64 = (el: HTMLImageElement) => {
      const canvas = document.createElement('canvas')
      const ctx = canvas.getContext('2d')
      canvas.width = el.width
      canvas.height = el.height
      ctx?.drawImage(el, 0, 0, canvas.width, canvas.height)
      return canvas.toDataURL('image/jpg')
    }
  })
}

使用hooks

<script setup lang="ts">
import BASE64 from './hooks'
BASE64({ el: '#img' }).then(resolve => {
  console.log(resolve.baseUrl)
})
</script>

(3)第三方hooks

安装依赖yarn add @vueuse/core
简单使用

<script setup lang="ts">
import { ref } from 'vue'
import { useDraggable } from '@vueuse/core'
const el = ref<HTMLElement | null>(null)
// `style` will be a helper computed for `left: ?px; top: ?px;`
const { x, y, style } = useDraggable(el, {
  initialValue: { x: 40, y: 40 }
})
</script>
<template>
  <div ref="el" :style="style" style="position: fixed">
    Drag me! I am at {{ x }}, {{ y }}
  </div>
</template>

组件间通讯

1.props父传子

父组件

<script setup >
import HelloWorld from './components/HelloWorld.vue'
</script>
<template>
  <HelloWorld msg="1"/>
</template>

子组件

<script setup>
// const props=defineProps(['msg'])
const props=defineProps({msg:String})
console.log(props.msg)
</script>

2.emit子传父

父组件

<script setup >
import HelloWorld from './components/HelloWorld.vue'
const getuser=(a)=>{
  console.log(a)
}
</script>
<template>
  <HelloWorld @getuser="getuser"/>
</template>

子组件

<script setup lang="ts">
const emit = defineEmits(['getuser'])
function buttonClick() {
  emit('getuser',1)
}
  </script>
<template>
  <button @click="buttonClick">传输</button>
</template>

自定义事件事件校检

<script setup>
const emit = defineEmits({
  // 没有校验
  click: null,
  // 校验 submit 事件
  submit: ({ email, password }) => {
    if (email && password) {
      return true
    } else {
      console.warn('Invalid submit event payload!')
      return false
    }
  }
})
function submitForm(email, password) {
  emit('submit', { email, password })
}
</script>

3.插槽通讯

(1)匿名插槽

子组件

<template>
  <!-- slot插槽占位 -->
 <slot></slot>
</template>

父组件

<script setup lang="ts">
import HelloWorld from "./components/HelloWorld.vue";
</script>
<template>
  <HelloWorld>
     插槽传递
  </HelloWorld>
</template>

(2)具名插槽

父组件

<script setup lang="ts">
import HelloWorld from "./components/HelloWorld.vue";
</script>
<template>
  <HelloWorld>
    <!-- v-slot:简写# -->
    <template v-slot:btn>
      <button>具名插槽</button>
    </template>
  </HelloWorld>
</template>

子组件

<template>
  <!-- slot插槽占位 -->
 <slot name="btn"></slot>
</template>

(3)作用域插槽

理解：数据在子组件的自身，但根据数据生成的结构需要父组件决定。
父组件

<script setup lang="ts">
import HelloWorld from "./components/HelloWorld.vue";
const person=[{name:'小明',age:18},{name:'小红',age:20}]
</script>
<template>
// 父组件将信息传递给子组件
<HelloWorld :person="person">
// 子组件接收父组件的插槽中传的值
  <template #tab="scope">
<tr v-for="(item,index) in scope.person" :key="index">
  <th>{{item.name}}</th>
  <th>{{item.age}}</th>
  <th><button >编辑</button></th>
</tr>
</template>
</HelloWorld>
</template>

子组件

<script setup lang="ts">
const props=defineProps<{person:{name:string,age:number}[]}>()
</script>
<template>
     <table border="1">
      <tr>
        <th>姓名</th>
        <th>年龄</th>
        <th>操作</th>
      </tr>
      <!-- 作用域插槽命名 -->
      // 向作用插槽中传值
      <slot name="tab" :person="props.person"></slot>
     </table>
</template>

4.依赖注入

父组件(祖先组件)

<!-- 依赖注入传的参可以在子组件中改变 -->
<template>
  <div class="App">
    <button>我是App</button>
    <A></A>
  </div>
</template>
<script setup lang="ts">
import { provide, ref } from 'vue'
import A from './components/Acom.vue'
let flag = ref<number>(1)
provide('flag', flag)
</script>

子组件(后代组件)

<template>
  <div>
    我是B
    <div>{{ flag }}</div>
    <button @click="flag++">+1</button>
  </div>
</template>
<script setup lang="ts">
import { inject, ref } from 'vue'
//  注入值，默认值(让其可以进行类型推断)
const flag = inject('flag', ref(1))
</script>

5.兄弟传参

(1)父组件当成一个桥梁

(2)发布订阅模式

Bus传递

type BusClass = {
  emit: (name: string) => void
  on: (name: string, callback: Function) => void
}
type PramsKey = string | number | symbol
type List = {
  [key: PramsKey]: Array<Function>
}
class Bus implements BusClass {
  list: List
  constructor() {
    this.list = {}
  }
  emit(name: string, ...args: Array<any>) {
    const evnentName: Array<Function> = this.list[name]
    evnentName.forEach(fn => {
      fn.apply(this, args)
    })
  }
  on(name: string, callback: Function) {
    const fn: Array<Function> = this.list[name] || []
    fn.push(callback)
    this.list[name] = fn
  }
}
export default new Bus()

A组件传递数值

<script setup lang="ts">
import { ref } from 'vue'
import Bus from '../utils/Bus'
const flag = ref(1)
const Pass = () => {
  Bus.emit('pass', flag)
}
</script>
<template>
  <div>
    我是A
    <div>{{ flag }}</div>
    <button @click="Pass">Pass</button>
  </div>
</template>
<style scoped lang="less"></style>

B组件接收数值

<script setup lang="ts">
import Bus from '../utils/Bus'
import { ref, type Ref } from 'vue'
const flag = ref(0)
Bus.on('pass', (Flag: Ref<number>) => {
  console.log(Flag)
  flag.value = Flag.value
})
</script>
<template>
  <div>
    我是B
    <div>{{ flag }}</div>
    <button @click="flag++">+</button>
  </div>
</template>
<style scoped lang="less"></style>

(3)第三方库mitt

安装yarn add mitt
全局挂载mit

import { createApp } from 'vue'
import { createPinia } from 'pinia'
import App from './App.vue'
import './assets/main.css'
import mitt from 'mitt'
const Mit = mitt()
const app = createApp(App)
// 类型声明
declare module 'vue' {
  export interface ComponentCustomProperties {
    $Bus: typeof Mit
  }
}
app.use(createPinia())
app.config.globalProperties.$Bus = Mit
app.mount('#app')

A组件传递数值

<script setup lang="ts">
import { getCurrentInstance, ref } from 'vue'
const instance = getCurrentInstance()
const flag = ref(1)
const Pass = () => {
  instance?.proxy?.$Bus.emit('pass', flag)
}
</script>
<template>
  <div>
    我是A
    <div>{{ flag }}</div>
    <button @click="Pass">Pass</button>
  </div>
</template>
<style scoped lang="less"></style>

B组件接收数值

<script setup lang="ts">
import { getCurrentInstance, ref, type Ref } from 'vue'
const instance = getCurrentInstance()
const flag = ref(0)
instance?.proxy?.$Bus.on('pass', Flag => {
  flag.value = (Flag as Ref<number>).value
})
</script>
<template>
  <div>
    我是B
    <div>{{ flag }}</div>
    <button @click="flag++">+</button>
  </div>
</template>
<style scoped lang="less"></style>

*监听事件

<script setup lang="ts">
import { getCurrentInstance, ref, type Ref } from 'vue'
const instance = getCurrentInstance()
const flag = ref(0)
/**
 * type:事件名称
 * Flag:传递参数
 */
instance?.proxy?.$Bus.on('*', (type, Flag) => {
  flag.value = (Flag as Ref<number>).value
})
</script>

取消监听事件

<script setup lang="ts">
import { getCurrentInstance, ref, type Ref } from 'vue'
const instance = getCurrentInstance()
const flag = ref(0)
instance?.proxy?.$Bus.off('pass', Flag => {
  flag.value = (Flag as Ref<number>).value
})
</script>

取消全部监听事件

<script setup lang="ts">
import { getCurrentInstance, ref, } from 'vue'
const instance = getCurrentInstance()
instance?.proxy?.$Bus.all.clear()
</script>

Typescript的支持

1.全局接口的抽取

src下定义types文件夹命名xx.d.ts
建立Person接口person.d.ts

interface personInterface{
    name:string
    age:number
}

组件中直接使用

<script setup lang="ts">
const props=defineProps<{person:personInterface[]}>()
</script>

如果不是在src下或src文件下的xx.d.ts文件则需要在tsconfig.json中配置

{
  {
 ...
  },
  "include": ["src/**/*.ts", "src/**/*.d.ts", "src/**/*.tsx", "src/**/*.vue"], //配置全局目录
  "references": [{ "path": "./tsconfig.node.json" }]
}

2.类型增强

使用环境：全局定义的数据，函数在vue组件中直接访问报错
index.html中定义数据

<!DOCTYPE html>
<html lang="en">
  <head>
  ...
  </head>
  <script>
    const  global=1
  </script>
  <body>
    ...
  </body>
</html>

定义类型增强

// common.d.ts
declare const global:string;

组件中直接读取

<script setup lang="ts">
console.log(global)
</script>

3.第三方库类型声明

安装一个库
安装库的ts类型声明@types/xxxx

4.props组件通讯TS

父组件

<script setup lang="ts">
import HelloWorld from './components/HelloWorld.vue'
</script>
<template>
  <HelloWorld msg="1"/>
</template>

子组件

<script setup lang="ts">
interface msgIterface{
  msg:string
}
const props = withDefaults(defineProps<msgIterface>(),{
	 msg:'默认值'
	})
console.log(props.msg)
</script>

5.emit组件通讯TS

父组件

<script setup lang="ts">
import HelloWorld from './components/HelloWorld.vue'
const getuser=(a:number)=>{
  console.log(a)
}
</script>
<template>
  <HelloWorld @getuser="getuser"/>
</template>
<style scoped>
</style>

子组件

<script setup lang="ts">
 const emit = defineEmits<{(e: 'getuser', id: number): void}>()
  // (e: 事件名, 键名：类型): void
function buttonClick() {
  emit('getuser',1)
}
  </script>
<template>
  <button @click="buttonClick">传输</button>
</template>
<style scoped>
</style>

6.依赖注入类型推断

父组件(祖先组件)

<template>
  <div class="App">
    <button>我是App</button>
    <A></A>
  </div>
</template>
<script setup lang="ts">
import { provide, ref } from 'vue'
import A from './components/Acom.vue'
let flag = ref<number>(1)
provide('flag', flag)
</script>

子组件(后代组件)

<template>
  <div>
    我是B
    <div>{{ flag }}</div>
    <button @click="flag++">+1</button>
  </div>
</template>
<script setup lang="ts">
import { inject, ref , type Ref} from 'vue'
//  注入值，默认值(让其可以进行类型推断)
const flag<Ref<number>> = inject('flag', ref(1))
</script>

7.定义全局函数和全局函数的类型支持

import { createApp } from 'vue'
...
const app = createApp(App)
type Fileter = {
  format: <T>(str: T) => string
}
declare module '@vue/runtime-core' {
  export interface ComponentCustomProperties {
    $filters: Fileter
    $env: string
  }
}
// 全局函数
app.config.globalProperties.$filters = {
  format<T>(str: T): string {
    return `真${str}`
  }
}
// 全局变量
app.config.globalProperties.$env = '全局变量'
...

脚手架Vite

1.基本使用

创建vue3的项目yarn create vite || npm init vite@latest
安装插件Volar

2.配置项目路径

tsconfig.json中添加

// 让ts可以识别这个路径
{
  "compilerOptions": {
   ...
    "baseUrl": "./",
    "paths": {
      "@/*":[
        "src/*"
      ]
    }
  },
  ...
}

vite.config.ts中添加


// https://vitejs.dev/config/
export default defineConfig({
  plugins: [vue()],
  resolve:{
    alias:{
      "@":join(__dirname,'src')
    }
  }
})

3.eslint和prettierrc的配置

.prettierrc.json

{
    "arrowParens": "always",
    "bracketSameLine": true,
    "bracketSpacing": true,
    "embeddedLanguageFormatting": "auto",
    "htmlWhitespaceSensitivity": "css",
    "insertPragma": false,
    "jsxSingleQuote": false,
    "printWidth": 120,
    "proseWrap": "never",
    "quoteProps": "as-needed",
    "requirePragma": false,
    "semi": false,
    "singleQuote": true,
    "tabWidth": 2,
    "trailingComma": "all",
    "useTabs": false,
    "vueIndentScriptAndStyle": false,
    "singleAttributePerLine": false
  }

.eslintrc.cjs

/* eslint-env node */
require('@rushstack/eslint-patch/modern-module-resolution')
module.exports = {
  root: true,
  extends: [
    'plugin:vue/vue3-essential',
    'eslint:recommended',
    '@vue/eslint-config-typescript',
    '@vue/eslint-config-prettier'
  ],
  rules: {
    'vue/multi-word-component-names': 'off', // 关闭命名
    semi: 0 // 结尾无分号
  },
  parserOptions: {
    ecmaVersion: 'latest'
  }
}

4.vite环境变量的配置

vite的环境在import中

<script setup lang="ts">
console.log(import.meta.env)
</script>

创建.env.development .env.production
package.json中配置运行生产环境,会自动注入

{
  ...
  "scripts": {
    "dev": "vite --mode development",
    ...
  },
}

vite.config.ts中读取环境变量

import { fileURLToPath, URL } from 'node:url'
import { defineConfig, loadEnv } from 'vite'
import unocss from 'unocss/vite'
import vue from '@vitejs/plugin-vue'
import { presetIcons, presetAttributify, presetUno } from 'unocss'
// https://vitejs.dev/config/
export default ({ mode }: any) => {
  // 读取环境变量
  console.log(loadEnv(mode, process.cwd()))
  return defineConfig({
    plugins: [vue()],
    resolve: {
      alias: {
        '@': fileURLToPath(new URL('./src', import.meta.url))
      }
    }
  })
}

找不到模块“./App.vue”或其相应的类型声明

declare module '*.vue' {
  import type { DefineComponent } from 'vue'
  // eslint-disable-next-line @typescript-eslint/no-explicit-any, @typescript-eslint/ban-types
  const component: DefineComponent<{}, {}, any>
  export default component
}

类型“ImportMeta”上不存在属性“env”

// tsconfig.json
{
  ...
  "compilerOptions": {
     ...
    "types": [ "vite/client" ],
  },
  ...
}

指令的重构

1.v-model指令

(1)v-model实现组件间数据双向绑定

父组件

<script setup lang="ts">
import HelloWorld from "./components/HelloWorld.vue";
import { ref } from "vue";
const num=ref(1)
</script>
<template>
  <HelloWorld v-model="num"/>
</template>

子组件

<script setup lang="ts">
import { computed } from 'vue';
const props=defineProps<{modelValue:number}>()
const emit = defineEmits<{(e: 'update:modelValue', id: number): void}>()
// 计算属性实现修改数据的同步
const value=computed({
  get(){
    return +props.modelValue
  },
  set(value){
    emit('update:modelValue',+value)
  }
})
</script>
<template>
 <input type="text"  v-model="value">
</template>

v-model的原理

<template>
<!-- <HelloWorld v-model="num"/> -->
  <HelloWorld :modelValue="num" @update:modelValue="num = $event"/>
</template>

(2)v-model传递特定的名称

父组件

<script setup lang="ts">
import { ref } from "vue";
import HelloWorld from "./components/HelloWorld.vue";
const num=ref(1)
</script>
<template>
  <!-- <HelloWorld :num="num @update:="num = $event""/> -->
  <HelloWorld v-model:num="num"/>
</template>

子组件

<script setup lang="ts">
import { computed } from 'vue';
const props=defineProps<{num:number}>()
const emit = defineEmits<{(e: 'update:num', id: number): void}>()
const value=computed({
  get(){
    return +props.num
  },
  set(value){
    emit('update:num',+value)
  }
})
</script>
<template>
 <input type="text"  v-model="value">
</template>

2.自定义指令

(1)自定义指令的简单使用

全局自定义指令

// mian.ts
import { createApp } from 'vue'
import './style.css'
import App from './App.vue'
const app=createApp(App)
app.directive('focus',{
    mounted(el){
     el.focus()
    }
   })
app.mount('#app')

使用自定义指令

<template>
 <input type="text"  v-model="value" v-focus>
</template>

局部自定义指令

<script setup>
// 在模板中启用 v-focus
const vFocus = {
  mounted: (el) => el.focus()
}
</script>
<template>
  <input v-focus />
</template>

(2)自定义指令详解

自定义指令的生命周期

<script setup lang="ts">
import type { Directive, DirectiveBinding } from 'vue'
type Dir = { background: string }
const vMove: Directive = {
  created() {}, //元素初始化的时候
  beforeMount() {}, //指令绑定到元素后调用 只调用一次
  mounted(el: HTMLElement, dir: DirectiveBinding<Dir>) {
    console.log(dir.value.background)
    el.style.background = dir.value.background
  }, //元素插入父级dom调用
  beforeUpdate() {}, //元素被更新之前调用
  updated() {}, //这个周期方法被移除 改用updated
  beforeUnmount() {}, //在元素被移除前调用
  unmounted() {} //指令被移除后调用 只调用一次
}
</script>
<template>
  <!-- 自定义指令，参数，修饰符 -->
  <div v-move:a.x="{ background: 'red' }">自定义指令</div>
</template>
<style scoped lang="less"></style>

生命周期的简写

<script setup lang="ts">
import type { Directive, DirectiveBinding } from 'vue'
type Dir = { background: string }
const vMove: Directive = (el: HTMLElement, dir: DirectiveBinding<Dir>) => {
  el.style.background = dir.value.background
}
</script>
<template>
  <!-- 自定义指令，参数，修饰符 -->
  <div v-move:a.x="{ background: 'red' }">自定义指令</div>
</template>
<style scoped lang="less"></style>

自定义拖拽指令

<script setup lang="ts">
import type { Directive } from 'vue'
const vMove: Directive = (el: HTMLElement) => {
  const move = (e: MouseEvent) => {
    console.log(e)
    el.style.left = e.clientX + 'px'
    el.style.top = e.clientY + 'px'
  }
  // 鼠标按下
  el.addEventListener('mousedown', () => {
    // 鼠标按下拖拽
    document.addEventListener('mousemove', move)
    // 鼠标松开
    document.addEventListener('mouseup', () => {
      // 清除事件
      document.removeEventListener('mousemove', move)
    })
  })
}
</script>
<template>
  <!-- 自定义指令，参数，修饰符 -->
  <div
    v-move
    style="
      background-color: red;
      width: 200px;
      height: 200px;
      position: fixed;
      left: 50%;
      top: 50%;
      transform: translate(-50%, -50%);
    "
  >
    <div style="background-color: black; width: 200px; color: white">
      自定义指令
    </div>
  </div>
</template>

响应式原理

1.了解Proxy

Proxy代理的get方法

    <script>
        let obj={
            name:'Vue',
            age:8
        }
        let obj2=new Proxy(obj,{
            /*
            *target表示obj这个对象
            *property表示读取的属性的key
            */
            get(target,property){
                console.log('执行了get');
                return target[property]
            }
        })
        console.log(obj2.age)
    </script>

Proxy代理的set方法

    <script>
        let obj={
            name:'Vue',
            age:8
        }
        let obj2=new Proxy(obj,{
            /*
            *target表示obj这个对象
            *property表示读取的属性的key
            *newValue表示设置的值
            */
            set(target,property,newValue){
                console.log('执行了set')
        target[property]=newValue
    }
        })
        obj2.age=7
        console.log(obj2.age)
    </script>

2.了解Object.defineProperty

Object.defineProperty(对象.定义属性,用来为一个对象添加新属性)

<script>
  let person = {
				name:'张三',
				sex:'男',
			}
			// 为 person对象 传输了一个新属性 “age”，并且设定它的值为 18
			Object.defineProperty(person,'age',{
				value=18
			})
			console.log(person)
</script>

Object.defineProperty属性的可枚举可修改的实现

<script>
  let person = {
				name:'张三',
				sex:'男',
			}
			// 为 person对象 传输了一个新属性 “age”，并且设定它的值为 18
			Object.defineProperty(person,'age',{
        enumerable=true  // 可枚举
        writable=true   // 可修改
        configurable:true // 可删除
				value=18
			})
			console.log(person)
</script>

Object.defineProperty() 的get()方法

 <script>
        let person = {
            name: '张三',
            sex: '男',
        }
        function Observer(obj) {
            const keys = Object.keys(obj)
            keys.forEach((key) => {
                Object.defineProperty(this,key,{
                    get() {
                        return obj[key]
                    }
                })
            })
        }
        const obs = new Observer(person)
        console.log(obs.sex);
    </script>

Object.defineProperty() 的set()方法

 <script>
        let person = {
            name: '张三',
            sex: '男',
        }
        function Observer(obj) {
            const keys = Object.keys(obj)
            keys.forEach((key) => {
                Object.defineProperty(this,key,{
                    set(val) {
                        console.log('set方法调用了')
                        obj[key] = val
                    }
                })
            })
        }
        const obs = new Observer(person)
        obs.name=15
    </script>

3.Vue双向绑定的实现的对比

Vue3的Proxy实现

<body>
    <input type="text" id="ipt">
    <p id='op'></p>
    <script>
        function reactive(obj) {
            return new Proxy(obj,{
                get(target,property) {
                    return target[property]
                },
                set(target,property,newVal) {
                    target[property] = newVal
                }
            })
        }
        let newObj = reactive([1,2])
        console.log(newObj[1])
        const ipt = document.querySelector('#ipt')
        ipt.value = newObj[1]
        document.querySelector('#op').innerHTML = newObj[1]
        ipt.addEventListener('input',function (e) {
            newObj[1] = e.target.value
            document.querySelector('#op').innerHTML = newObj[1]
        })
    </script>
</body>

Vue2的Object.defineProperty实现

<body>
    <input type="text" id="ipt">
    <p id='op'></p>
    <script>
        function Observer(obj) {
            const keys = Object.keys(obj)
            keys.forEach((key) => {
                Object.defineProperty(this,key,{
                    get() {
                        console.log('get方法被调用了');
                        return obj[key]
                    },
                    set(val) {
                        console.log('set方法调用了')
                        obj[key] = val
                    }
                })
            })
        }
        const obs = new Observer([1,2,3])
        const ipt = document.querySelector('#ipt')
        ipt.value = obs[1]
        document.querySelector('#op').innerHTML = obs[1]
        ipt.addEventListener('input',function (e) {
            obs[1] = e.target.value
            document.querySelector('#op').innerHTML = obs[1]
        })
    </script>
</body>

上面的测试，Object.property是可以检测到通过索引改变数组的操作的，而Vue没有实现,Object.defineProperty表示这个锅我不背

内置组件

1.内置组件

(1)Teleport组件

可以将一个组件内部的一部分模板“传送”到该组件的 DOM 结构外层的位置去
父组件

<!-- 遮罩层组件传送到body下 -->
<script setup lang="ts">
import Acom from './components/Acom.vue'
</script>
<template>
<div class="app"></div>
<Acom/>
</template>
<style scoped >
.app{
  width: 200px;
  height: 200px;
  background-color: pink;
}
</style>

子组件

<script setup lang="ts">
  import { ref } from 'vue'
  const open = ref(false)
  </script>
  <template>
    <button @click="open=true">显示遮罩层</button>
    <!-- 传送到body -->
  <Teleport to="body">
    <div class="cover" v-show="open">
      <span @click="open=false"> X</span>
   </div>
  </Teleport>
  </template>
  <style scoped>
  .cover {
   position: absolute;
   z-index:2;
   top: 0;
   left: 0;
   bottom: 0;
   right: 0;
   background-color: rgba(0,0,0,0.5);
  }
  </style>

(2)Transition组件

非命名动画

<script setup lang="ts">
import { ref } from 'vue';
const show=ref(true)
</script>
<template>
<button @click="show=!show">显示/隐藏</button>
<Transition>
<div class="div" v-if="show"></div>
</Transition>
</template>
<style scoped>
.div{
  background-color: pink;
  width: 200px;
  height: 200px;
  margin: auto;
}
.v-enter-active,
.v-leave-active {
  transition: opacity 0.5s ease;
}
.v-enter-from,
.v-leave-to {
  opacity: 0;
}
</style>

命名动画

<script setup lang="ts">
import { ref } from 'vue';
const show=ref(true)
</script>
<template>
<button @click="show=!show">显示/隐藏</button>
<Transition name="fade">
<div class="div" v-if="show"></div>
</Transition>
</template>
<style scoped>
.div{
  background-color: pink;
  width: 200px;
  height: 200px;
  margin: auto;
}
.fade-enter-active {
  transition: all 0.3s ease-out;
}
.fade-leave-active {
  transition: all 0.8s cubic-bezier(1, 0.5, 0.8, 1);
}
.fade-enter-from,
.fade-leave-to {
  transform: translateX(20px);
  opacity: 0;
}
</style>

过度动画

<Transition mode="out-in">
  ...
</Transition>

结合第三方库Animate.css

<!--  yarn add animate.css -->
<script setup lang="ts">
import { ref } from 'vue'
import 'animate.css'
import Acom from './components/Acom.vue'
const show = ref(true)
</script>
<template>
  <transition
    leave-active-class="animate__animated animate__fadeOut"
    enter-active-class="animate__animated animate__fadeIn"
  >
    <Acom v-if="show"></Acom>
  </transition>
  <button @click="show = !show">显示/隐藏</button>
</template>
<style scoped lang="less"></style>

transition 生命周期

<script setup lang="ts">
import { ref } from 'vue'
import 'animate.css'
import Acom from './components/Acom.vue'
const show = ref(true)
const beforeEnter = () => {
  console.log('进入之前')
}
const enter = (_, done: Function) => {
  console.log('过度曲线')
  setTimeout(() => {
    done()
  }, 3000)
}
const afterEnter = () => {
  console.log('过度完成')
}
const enterCancelled = () => {
  console.log('进入效果被打断')
}
const beforeLeave = () => {
  console.log('离开之前')
}
const leave = (_, done: Function) => {
  setTimeout(() => {
    done()
  }, 3000)
  console.log('过度曲线')
}
const afterLeave = () => {
  console.log('离开之后')
}
const leaveCancelled = () => {
  console.log('离开效果被打断')
}
</script>
<template>
  <transition
    leave-active-class="animate__animated animate__fadeOut"
    enter-active-class="animate__animated animate__fadeIn"
    @before-enter="beforeEnter"
    @enter="enter"
    @after-enter="afterEnter"
    @enter-cancelled="enterCancelled"
    @before-leave="beforeLeave"
    @leave="leave"
    @after-leave="afterLeave"
    @leave-cancelled="leaveCancelled"
  >
    <Acom v-if="show"></Acom>
  </transition>
  <button @click="show = !show">显示/隐藏</button>
</template>

生命周期结合第三方库gsap.js

<!-- yarn add  gsap -->
<script setup lang="ts">
import { ref } from 'vue'
import Acom from './components/Acom.vue'
import gsap from 'gsap'
const show = ref(true)
// 进入之前
const beforeEnter = (el: Element) => {
  gsap.set(el, {
    width: 0,
    height: 0
  })
}
// 进入过度动画
const enter = (el: Element, done: gsap.Callback) => {
  gsap.to(el, {
    width: 200,
    height: 200,
    onComplete: done
  })
}
// 离开之前
const beforeLeave = (el: Element) => {
  gsap.set(el, {
    width: 200,
    height: 200
  })
}
// 进入过度动画
const leave = (el: Element, done: gsap.Callback) => {
  gsap.to(el, {
    width: 0,
    height: 0,
    onComplete: done
  })
}
</script>
<template>
  <transition
    @before-enter="beforeEnter"
    @enter="enter"
    @before-leave="beforeLeave"
    @leave="leave"
  >
    <Acom v-if="show"></Acom>
  </transition>
  <button @click="show = !show">显示/隐藏</button>
</template>

初始化动画

<script setup lang="ts">
import { ref } from 'vue'
import Acom from './components/Acom.vue'
const show = ref(true)
</script>
<template>
  <transition
    appear-from-class="from"
    appear-active-class="active"
    appear-to-class="to"
    appear
  >
    <Acom v-if="show"></Acom>
  </transition>
  <button @click="show = !show">显示/隐藏</button>
</template>
<style scoped>
.from {
  /* 初始化之前 */
  width: 0;
  height: 0;
}
.active {
  /* 过度动画 */
  transition: all 2s ease;
}
.to {
  /* 初始化完成 */
  width: 200px;
  height: 200px;
}
</style>

初始化动画结合Animate.css

<script setup lang="ts">
import { ref } from 'vue'
import Acom from './components/Acom.vue'
import 'animate.css'
const show = ref(true)
</script>
<template>
  <transition appear-active-class="animate__animated animate__heartBeat" appear>
    <Acom v-if="show"></Acom>
  </transition>
  <button @click="show = !show">显示/隐藏</button>
</template>
<style scoped></style>

(3)transition-group过度列表

Transition组件无法对v-for的列表进行渲染
transition-group的tag属性

<!-- tag属性可以让transition-group多加一层节点元素 -->
<template>
  <div class="wraps">
    <transition-group tag="session">
      <!-- 使用transition-group渲染的组件要有key-->
      <div class="item" v-for="item in 5" :key="item">{{ item }}</div>
    </transition-group>
  </div>
</template>

添加列表时的动画效果

<script setup lang="ts">
import { ref } from 'vue'
import 'animate.css'
const num = ref(5)
</script>
<template>
  <div class="wraps">
    <transition-group
      leave-active-class="animate__animated animate__fadeOut"
      enter-active-class="animate__animated animate__fadeIn"
    >
      <!-- 使用transition-group渲染的组件要有key-->
      <div class="item" v-for="item in num" :key="item">{{ item }}</div>
    </transition-group>
  </div>
  <button @click="num++">添加</button>
  <button @click="num--">删除</button>
</template>
<style scoped lang="less">
.wraps {
  display: flex;
  flex-wrap: wrap;
  word-break: break-all;
  border: 1px solid #ccc;
  .item {
    margin: 10px;
  }
}
</style>

平移动画move-class

<script setup lang="ts">
import { ref } from 'vue'
import _ from 'lodash'
// 建立9x9数组
let list = ref(
  Array.apply(null, { length: 81 } as number[]).map((_, index) => {
    return {
      id: index,
      number: (index % 9) + 1
    }
  })
)
// 打乱数组
const random = () => {
  list.value = _.shuffle(list.value)
}
console.log(list)
</script>
<template>
  <div>
    <button @click="random">打乱</button>
    <transition-group tag="div" class="wraps" move-class="move">
      <div v-for="item in list" :key="item.id" class="item">
        {{ item.number }}
      </div>
    </transition-group>
  </div>
</template>
<style scoped lang="less">
.wraps {
  display: flex;
  flex-wrap: wrap; // 换行
  width: calc(25px * 10 + 9px);
  .item {
    width: 25px;
    height: 25px;
    border: 1px solid #ccc;
    text-align: center;
  }
}
.move {
  transition: all 1s;
}
</style>

状态过度(数字过度颜色过度)

<script setup lang="ts">
import { reactive, watch } from 'vue'
import gsap from 'gsap'
const num = reactive({
  current: 0,
  tweenedNumber: 0
})
watch(
  () => num.current,
  newVal => {
    gsap.to(num, {
      duration: 1, // 过度时间
      tweenedNumber: newVal
    })
  }
)
</script>
<template>
  <div>
    <input type="text" v-model="num.current" step="20" />
    <div>
      <!-- 去掉小数点 -->
      {{ num.tweenedNumber.toFixed(0) }}
    </div>
  </div>
</template>
<style scoped lang="less"></style>

(4)keep-alive组件

开启keep-alive 生命周期的变化

初次进入时： onMounted-> onActivated
退出后触发:  deactivated

缓存数据

<script setup lang="ts">
import { ref } from 'vue'
import Acom from './components/Acom.vue'
const show = ref(true)
</script>
<template>
  <keep-alive>
    <Acom v-if="show"></Acom>
  </keep-alive>
  <button @click="show = !show">显示/隐藏</button>
</template>

include属性和exclude属性

<!-- 注意组件一定要命名才可以使用include -->
<script setup lang="ts">
import { ref } from 'vue'
import Acom from './components/Acom.vue'
import Bcom from './components/Bcom.vue'
const show = ref(true)
</script>
<template>
  <keep-alive :include="['Acom']" :exclude="['Bcom']">
    <Acom v-if="show"></Acom>
    <Bcom v-else></Bcom>
  </keep-alive>
  <button @click="show = !show">显示/隐藏</button>
</template>
<style scoped lang="less"></style>

2.普通组件

(1)全局组件

配置全局组件

import { createApp } from 'vue'
import { createPinia } from 'pinia'
import App from './App.vue'
import Acom from './components/Acom.vue'
import './assets/main.css'
const app = createApp(App)
app.use(createPinia())
app.component('Acom', Acom)
app.mount('#app')

使用组件

<template>
  <div>
    <Acom></Acom>
  </div>
</template>

(2)异步组件

子组件中发送了请求变成异步

<script setup lang="ts">
interface ResItf {
  code: number
  data: { a: number; b: number }[]
  message: string
}
let p: Promise<ResItf> = new Promise(resolve => {
  setTimeout(() => {}, 3000)
  resolve({
    code: 0,
    data: [
      { a: 1, b: 2 },
      { a: 11, b: 22 }
    ],
    message: ''
  })
})
const a = await p
console.log(a)
</script>
<template>
  <div>异步组件</div>
  <div>异步组件</div>
  <div>异步组件</div>
</template>

父组件异步调用组件

<script setup lang="ts">
// 异步组件不能这样引入
// import Acom from './components/Acom.vue'
import { defineAsyncComponent } from 'vue'
const Acom = defineAsyncComponent(() => import('./components/Acom.vue'))
</script>
<template>
  <div>
    <Suspense>
      <template #default>
        <Acom></Acom>
      </template>
      <template #fallback> 加载中。。。 </template>
    </Suspense>
  </div>
</template>
<style scoped lang="less"></style>

语法糖组件命名问题

安装依赖yarn add vite-plugin-vue-setup-extend
直接命名

<script lang="ts" setup name="xxx">
</script>

常用的CSS的功能

样式穿透

<style scoped lang="less">
:deep(input) {
  color: red;
}
</style>

插槽选择器

<template>
  <div>
    <slot name="nums" :nums="['1', '2', '3']"> </slot>
  </div>
</template>
<style scoped lang="less">
:slotted(.li) {
  color: red;
}
</style>

全局选择器

<script setup lang="ts"></script>
<template>
  <div>
    <slot name="nums" :nums="['1', '2', '3']"> </slot>
  </div>
</template>
<style scoped lang="less">
:global(.li) {
  color: red;
}
</style>

动态CSS

<script setup lang="ts">
import { reactive } from 'vue'
const style = reactive({
  color: 'red'
})
setTimeout(() => {
  style.color = 'blue'
}, 3000)
</script>
<template>
  <div class="div">动态css</div>
</template>
<style scoped lang="less">
.div {
  color: v-bind('style.color');
}
</style>

1.CSS原子化

安装unocssyarn add unocss
vite的配置文件中配置

import { fileURLToPath, URL } from 'node:url'
import pxtoViewPort from 'postcss-px-to-viewport'
import { defineConfig } from 'vite'
import unocss from 'unocss/vite'
import vue from '@vitejs/plugin-vue'
// https://vitejs.dev/config/
export default defineConfig({
  plugins: [
    vue(),
    // 配置的原子化
    unocss({
      rules: [
        ['flex', { display: 'flex' }],
        ['red', { color: 'red' }],
        [/^m-(\d+)$/, ([, d]) => ({ margin: `${Number(d) * 10}px` })]
      ]
    })
  ],
  resolve: {
    alias: {
      '@': fileURLToPath(new URL('./src', import.meta.url))
    }
  }
})

main.ts中引入import 'uno.css'
其他预设配置中引入

import { fileURLToPath, URL } from 'node:url'
import { defineConfig } from 'vite'
import unocss from 'unocss/vite'
import vue from '@vitejs/plugin-vue'
import { presetIcons, presetAttributify, presetUno } from 'unocss'
// https://vitejs.dev/config/
export default defineConfig({
  plugins: [
    vue(),
    unocss({
      // 预设
      presets: [presetIcons(), presetAttributify(), presetUno()],
      rules: [
        ['flex', { display: 'flex' }],
        ['red', { color: 'red' }],
        [/^m-(\d+)$/, ([, d]) => ({ margin: `${Number(d) * 10}px` })]
      ]
    })
  ],
  resolve: {
    alias: {
      '@': fileURLToPath(new URL('./src', import.meta.url))
    }
  }
})

第一预设图标库

npm i -D @iconify-json/ic
// 后缀ic是选择的图标库

第二预设属性语义化无须class

 <div color="red">left</div>

第三预设

默认的 @unocss/preset-uno 预设（实验阶段）是一系列流行的原子化框架的 通用超集，
包括了 Tailwind CSS，Windi CSS，Bootstrap，Tachyons 等。
例如，ml-3（Tailwind），ms-2（Bootstrap），ma4（Tachyons），mt-10px（Windi CSS）均会生效。

5.Vue3集成Tailwind CSS

安装依赖yarn add -D tailwindcss@latest postcss@latest autoprefixer@latest
安装插件tailwind css inteliSence
生成配置文件npx tailwindcss init -p
tailwind.config.js配置文件中添加

/** @type {import('tailwindcss').Config} */
module.exports = {
  content: ['./index.html', './src/**/*.{vue,js,ts,jsx,tsx}'],
  theme: {
    extend: {}
  },
  plugins: []
}

创建index.css文件并且在mian.ts中引入

@tailwind base;
@tailwind components;
@tailwind utilities;

使用tailwindcss的样式

<script setup lang="ts"></script>
<template>
  <div
    class="w-screen h-screen bg-red-600 flex justify-center items-center text-8xl text-teal-50"
  >
    hello tailwind
  </div>
</template>
<style scoped lang="less"></style>

面试常用源码

1.app.use()的源码实现

实现myuse

import type { App } from 'vue'
import { app } from '../main'
interface Use {
  install: (app: App, ...options: any[]) => void
}
// 插件注册的数组
const installList = new Set()
export function MyUse<T extends Use>(plugin: T, ...options: any[]) {
  if (installList.has(plugin)) {
    console.log('插件件已经注册')
    return
  }
  plugin.install(app, ...options)
  installList.add(plugin)
}

使用myuse调用插件

import { createApp } from 'vue'
import { createPinia } from 'pinia'
import App from './App.vue'
import './assets/main.css'
import Loading from './components/Loading'
import { MyUse } from './utils/myuse'
export const app = createApp(App)
// 使用插件
// app.use(Loading)
MyUse(Loading)
app.use(createPinia())
app.mount('#app')
type Lod = {
  show: () => void
  hide: () => void
}
//编写ts loading 声明文件放置报错 和 智能提示
declare module '@vue/runtime-core' {
  export interface ComponentCustomProperties {
    $loading: Lod
  }
}

移动端适配

1.第一种适配方案

安装依赖yarn add amfe-flexible postcss postcss-pxtorem@5.1.1
main.ts引入amfe-flexibleimport "amfe-flexible"
根目录下创建postcss.config.js文件并配置

module.exports = {
  plugins: {
    'postcss-pxtorem': {
      // 能够把所有元素的px单位转成Rem
      // rootValue: 转换px的基准值。
      // 编码时, 一个元素宽是75px，则换成rem之后就是2rem
      rootValue: 37.5,
      propList: ['*']
    }
  }
}

2.第二种适配方案

安装依赖yarn add postcss-px-to-viewport -D
vite.config.ts内置postcss.config.js中修改配置

import { fileURLToPath, URL } from 'node:url'
import pxtoViewPort from 'postcss-px-to-viewport'
import { defineConfig } from 'vite'
import vue from '@vitejs/plugin-vue'
// https://vitejs.dev/config/
export default defineConfig({
  plugins: [vue()],
  css: {
    postcss: {
      plugins: [
     // postcss-px-to-viewport的配置
        pxtoViewPort({
          unitToConvert: 'px', // 要转化的单位
          viewportWidth: 750, // UI设计稿的宽度
          unitPrecision: 6, // 转换后的精度，即小数点位数
          propList: ['*'], // 指定转换的css属性的单位，*代表全部css属性的单位都进行转换
          viewportUnit: 'vw', // 指定需要转换成的视窗单位，默认vw
          fontViewportUnit: 'vw', // 指定字体需要转换成的视窗单位，默认vw
          selectorBlackList: ['ignore-'], // 指定不转换为视窗单位的类名，
          minPixelValue: 1, // 默认值1，小于或等于1px则不进行转换
          mediaQuery: true, // 是否在媒体查询的css代码中也进行转换，默认false
          replace: true, // 是否转换后直接更换属性值
          landscape: false // 是否处理横屏情况
        })
      ]
    }
  },
  resolve: {
    alias: {
      '@': fileURLToPath(new URL('./src', import.meta.url))
    }
  }
})

创建postcss-px-to-viewport.d.ts的声明文件

declare module 'postcss-px-to-viewport' {
  type Options = {
    unitToConvert: 'px' | 'rem' | 'cm' | 'em'
    viewportWidth: number
    viewportHeight: number // not now used; TODO: need for different units and math for different properties
    unitPrecision: number
    viewportUnit: string
    fontViewportUnit: string // vmin is more suitable.
    selectorBlackList: string[]
    propList: string[]
    minPixelValue: number
    mediaQuery: boolean
    replace: boolean
    landscape: boolean
    landscapeUnit: string
    landscapeWidth: number
  }
  export default function (options: Partial<Options>): any
}

在tsconfig.json中引入声明文件

{
  "extends": "@vue/tsconfig/tsconfig.web.json",
  "include": ["env.d.ts", "src/**/*", "src/**/*.vue", "postcss-px-to-viewport.d.ts"],
  "compilerOptions": {
    "baseUrl": ".",
    "types": ["element-plus/global"],
    "paths": {
      "@/*": ["./src/*"]
    }
  },
  "references": [
    {
      "path": "./tsconfig.config.json"
    }
  ]
}

注意:如果外面用到了postcss.config.js，在postcss.config.js中添加配置文件

// 要禁用vite.config.ts内置postcss.config.js
module.exports = {
  plugins: {
    tailwindcss: {},
    autoprefixer: {},
    'postcss-px-to-viewport': {
      unitToConvert: 'px', // 要转化的单位
      viewportWidth: 320 // UI设计稿的宽度
      // unitPrecision: 6, // 转换后的精度，即小数点位数
      // propList: ['*'], // 指定转换的css属性的单位，*代表全部css属性的单位都进行转换
      // viewportUnit: 'vw', // 指定需要转换成的视窗单位，默认vw
      // fontViewportUnit: 'vw', // 指定字体需要转换成的视窗单位，默认vw
      // selectorBlackList: ['wrap'], // 指定不转换为视窗单位的类名，
      // minPixelValue: 1, // 默认值1，小于或等于1px则不进行转换
      // mediaQuery: true, // 是否在媒体查询的css代码中也进行转换，默认false
      // replace: true, // 是否转换后直接更换属性值
      // exclude: [/node_modules/], // 设置忽略文件，用正则做目录名匹配
      // landscape: false // 是否处理横屏情况
    }
  }
}

的其他知识点

1.全局函数和全局变量

全局函数

import { createApp } from 'vue'
import { createPinia } from 'pinia'
import App from './App.vue'
import './assets/main.css'
const app = createApp(App)
type Fileter = {
  format: <T>(str: T) => string
}
declare module '@vue/runtime-core' {
  export interface ComponentCustomProperties {
    $filters: Fileter
  }
}
// 全局函数
app.config.globalProperties.$filters = {
  format<T>(str: T): string {
    return `真${str}`
  }
}
app.use(createPinia())
app.mount('#app')

全局变量

import { createApp } from 'vue'
import { createPinia } from 'pinia'
import App from './App.vue'
import './assets/main.css'
const app = createApp(App)
declare module '@vue/runtime-core' {
  export interface ComponentCustomProperties {
    $env: string
  }
}
// 全局变量
app.config.globalProperties.$env = '全局变量'
app.use(createPinia())
app.mount('#app')

2.自定义插件

封装插件的样式，抛出插件的显示隐藏方法

<script setup lang="ts">
import { ref } from 'vue'
const isShow = ref(false)
// 控制load显示
const show = () => {
  console.log(111)
  isShow.value = true
}
const hide = () => {
  isShow.value = false
}
// 这里抛出的东西会在插件声明文件中调用
defineExpose({
  show,
  hide
})
</script>
<template>
  <div v-if="isShow" class="loading">loading....</div>
</template>
<style scoped lang="less"></style>

创建接收调用插件的方法

import { render, type App, type VNode } from 'vue'
import Loading from './index.vue'
import { createVNode } from 'vue'
export default {
  install(app: App) {
    // 变成div
    const Vnode: VNode = createVNode(Loading)
    // 挂载
    render(Vnode, document.body)
    // console.log(app, Vnode)
    // // 读取loading组件中导出的方法
    // console.log(Vnode.component?.exposed.show)
    // 对插件的方法进行全局挂载
    app.config.globalProperties.$loading = {
      show: Vnode.component?.exposed?.show,
      hide: Vnode.component?.exposed?.hide
    }
  }
}

main.ts中挂载上面的方方法

import { createApp } from 'vue'
import { createPinia } from 'pinia'
import App from './App.vue'
import './assets/main.css'
import Loading from './components/Loading'
const app = createApp(App)
// 使用插件
app.use(Loading)
app.use(createPinia())
app.mount('#app')

对插件的方法进行声明

type Lod = {
  show: () => void
  hide: () => void
}
//编写ts loading 声明文件放置报错 和 智能提示
declare module '@vue/runtime-core' {
  export interface ComponentCustomProperties {
    $loading: Lod
  }
}

使用插件

<script setup lang="ts">
import { getCurrentInstance } from 'vue'
const instance = getCurrentInstance()
// 调用插件
instance?.proxy?.$loading.show()
// 5秒关闭插件
setTimeout(() => {
  instance?.proxy?.$loading.hide()
}, 5000)
</script>
<template>
  <div></div>
</template>
<style scoped lang="less"></style>

3.函数式编程

h函数

h 接收三个参数
1.type 元素的类型
2.propsOrChildren 数据对象, 这里主要表示(props, attrs, dom props, class 和 style)
3.children 子节点

h函数的多种组合

// 除类型之外的所有参数都是可选的
h('div')
h('div', { id: 'foo' })
//属性和属性都可以在道具中使用
//Vue会自动选择正确的分配方式
h('div', { class: 'bar', innerHTML: 'hello' })
// props modifiers such as .prop and .attr can be added
// with '.' and `^' prefixes respectively
h('div', { '.name': 'some-name', '^width': '100' })
// class 和 style 可以是对象或者数组
h('div', { class: [foo, { bar }], style: { color: 'red' } })
// 定义事件需要加on 如 onXxx
h('div', { onClick: () => {} })
// 子集可以字符串
h('div', { id: 'foo' }, 'hello')
//如果没有props是可以省略props 的
h('div', 'hello')
h('div', [h('span', 'hello')])
// 子数组可以包含混合的VNode和字符串
h('div', ['hello', h('span', 'hello')])

使用props传递参数

<template>
    <Btn text="按钮"></Btn>
</template>
<script setup lang='ts'>
import { h, } from 'vue';
type Props = {
    text: string
}
const Btn = (props: Props, ctx: any) => {
    return h('div', {
        class: 'p-2.5 text-white bg-green-500 rounded shadow-lg w-20 text-center inline m-1',
    }, props.text)
}
</script>

接收emit

<template>
    <Btn @on-click="getNum" text="按钮"></Btn>
</template>
<script setup lang='ts'>
import { h, } from 'vue';
type Props = {
    text: string
}
const Btn = (props: Props, ctx: any) => {
    return h('div', {
        class: 'p-2.5 text-white bg-green-500 rounded shadow-lg w-20 text-center inline m-1',
        onClick: () => {
            ctx.emit('on-click', 123)
        }
    }, props.text)
}
const getNum = (num: number) => {
    console.log(num);
}
</script>

定义插槽

<template>
    <Btn @on-click="getNum">
        <template #default>
            按钮slots
        </template>
    </Btn>
</template>
<script setup lang='ts'>
import { h, } from 'vue';
type Props = {
    text?: string
}
const Btn = (props: Props, ctx: any) => {
    return h('div', {
        class: 'p-2.5 text-white bg-green-500 rounded shadow-lg w-20 text-center inline m-1',
        onClick: () => {
            ctx.emit('on-click', 123)
        }
    }, ctx.slots.default())
}
const getNum = (num: number) => {
    console.log(num);
}
</script>

4.vue性能优化

(1)跑分和打包体积

跑分vue开发工具Lighthouse

从Performance页的表现结果来看，得分37分，并提供了很多的时间信息，我们来解释下这些选项代表的意思：
FCP (First Contentful Paint)：首次内容绘制的时间，浏览器第一次绘制DOM相关的内容，也是用户第一次看到页面内容的时间。
Speed Index: 页面各个可见部分的显示平均时间，当我们的页面上存在轮播图或者需要从后端获取内容加载时，这个数据会被影响到。
LCP (Largest Contentful Paint)：最大内容绘制时间，页面最大的元素绘制完成的时间。
TTI（Time to Interactive）：从页面开始渲染到用户可以与页面进行交互的时间，内容必须渲染完毕，交互元素绑定的事件已经注册完成。
TBT（Total Blocking Time）：记录了首次内容绘制到用户可交互之间的时间，这段时间内，主进程被阻塞，会阻碍用户的交互，页面点击无反应。
CLS（Cumulative Layout Shift）：计算布局偏移值得分，会比较两次渲染帧的内容偏移情况，可能导致用户想点击A按钮，但下一帧中，A按钮被挤到旁边，导致用户实际点击了B按钮。

打包后rollup的插件yarn add rollup-plugin-visualizer

import { fileURLToPath, URL } from 'node:url'
import { defineConfig, loadEnv } from 'vite'
import unocss from 'unocss/vite'
import vue from '@vitejs/plugin-vue'
import { visualizer } from 'rollup-plugin-visualizer'
// https://vitejs.dev/config/
export default ({ mode }: any) => {
  console.log(loadEnv(mode, process.cwd()))
  return defineConfig({
    plugins: [vue(), 
    // 配置rollup的插件
    visualizer({ open: true })],
    resolve: {
      alias: {
        '@': fileURLToPath(new URL('./src', import.meta.url))
      }
    }
  })
}

vite配置文件中vite的优化

import { fileURLToPath, URL } from "node:url";
import { defineConfig } from "vite";
import vue from "@vitejs/plugin-vue";
import vueJsx from "@vitejs/plugin-vue-jsx";
// https://vitejs.dev/config/
export default  defineConfig({
    ...
    build: {
      chunkSizeWarningLimit: 2000,
      cssCodeSplit: true, //css 拆分
      sourcemap: false, //不生成sourcemap
      minify: 'terser', //是否禁用最小化混淆，esbuild打包速度最快，terser打包体积最小。
      assetsInlineLimit: 5000 //小于该值 图片将打包成Base64
    }
  })

(2)PWA离线存储技术

安装依赖yarn add vite-plugin-pwa -D
配置

import { fileURLToPath, URL } from "node:url";
import { VitePWA } from "vite-plugin-pwa";
import { defineConfig } from "vite";
import vue from "@vitejs/plugin-vue";
import vueJsx from "@vitejs/plugin-vue-jsx";
// https://vitejs.dev/config/
export default defineConfig({
  plugins: [
    vue(),
    vueJsx(),
    VitePWA({
      workbox: {
        cacheId: "key", //缓存名称
        runtimeCaching: [
          {
            urlPattern: /.*\.js.*/, //缓存文件
            handler: "StaleWhileRevalidate", //重新验证时失效
            options: {
              cacheName: "XiaoMan-js", //缓存js，名称
              expiration: {
                maxEntries: 30, //缓存文件数量 LRU算法
                maxAgeSeconds: 30 * 24 * 60 * 60, //缓存有效期
              },
            },
          },
        ],
      },
    }),
  ],
  ....
});

(3)其他性能优化

图片懒加载

import { createApp } from 'vue'
import App from './app'
import lazyPlugin from 'vue3-lazy'
const app = createApp(App)
app.use(lazyPlugin, {
  loading: 'loading.png',
  error: 'error.png'
})
app.mount('#app')
<img v-lazy="user.avatar" >

虚拟列表实现

后台返回多数据
展示可视区的dom

多线程使用 new Worker 创建

// worker脚本与主进程的脚本必须遵守同源限制。他们所在的路径协议、域名、端口号三者需要相同
const myWorker1 = new Worker("./calcBox.js");
// 都使用postMessage发送消息
worker.postMessage(arrayBuffer, [arrayBuffer]);
// 都使用onmessage接收消息
self.onmessage = function (e) {
// xxx这里是worker脚本的内容
};
关闭
worker.terminate();

防抖节流

标签 ts, vue3, 教程

Vue3+TS教程

Vue3

组合式API

1.钩子函数steup

2.响应式API

3.计算属性API

4.监听属性API

5.高级监听API

6.响应式对象解构API

7.生命周期API

8.ref获取dom

9.Hooks

(1)官方hooks

(2)自定hooks

(3)第三方hooks

组件间通讯

1.props父传子

2.emit子传父

3.插槽通讯

(1)匿名插槽

(2)具名插槽

(3)作用域插槽

4.依赖注入

5.兄弟传参

(1)父组件当成一个桥梁

(2)发布订阅模式

(3)第三方库mitt

Typescript的支持

1.全局接口的抽取

2.类型增强

3.第三方库类型声明

4.props组件通讯TS

5.emit组件通讯TS

6.依赖注入类型推断

7.定义全局函数和全局函数的类型支持

脚手架Vite

1.基本使用

2.配置项目路径

3.eslint和prettierrc的配置

4.vite环境变量的配置

指令的重构

1.v-model指令

(1)v-model实现组件间数据双向绑定

(2)v-model传递特定的名称

2.自定义指令

(1)自定义指令的简单使用

(2)自定义指令详解

响应式原理

1.了解Proxy

2.了解Object.defineProperty

3.Vue双向绑定的实现的对比

内置组件

1.内置组件

(1)Teleport组件

(2)Transition组件

(3)transition-group过度列表

(4)keep-alive组件

2.普通组件

(1)全局组件

(2)异步组件

语法糖组件命名问题

常用的CSS的功能

1.CSS原子化

5.Vue3集成Tailwind CSS

面试常用源码

1.app.use()的源码实现

移动端适配

1.第一种适配方案

2.第二种适配方案

的其他知识点

1.全局函数和全局变量

2.自定义插件

3.函数式编程

4.vue性能优化

(1)跑分和打包体积

(2)PWA离线存储技术

(3)其他性能优化