Devue3 development

Front end development blog 2020-11-08 19:27:13
devue3 devue development


author :vita2333
link :https://juejin.im/post/689231...

I've been looking forward to vue3, As soon as it was released, I started to experience , Here is a record of a few of the unusual small holes on the Internet ~

Custom global parameters

Definition :

// main.js
const app = createApp(App)
app.config.globalProperties.$test = 'test'

except setup() You need to get the instance first , Other places can go directly through $test Use :

<tempalte>
<div>{{ $test }}</div>
</tempalte>
<script>
import { getCurrentInstance } from 'vue'
export default {
setup() {
const test = getCurrentInstance()?.appContext.config.globalProperties.$test
console.log('test===')
console.log(test)
},
}
</script>

Vite adopt alias Alias reference

stay webpack in , To configure src Its alias is @, It can be written like this :

// quote src/views/PageOne.vue
import PageOne from '@/views/PageOne.vue'
Copy code 

If you use Vite, You need to make the following changes :

// vite.config.js
module.exports={
alias: {
'/@/': path.resolve(__dirname, './src'),
},
}
// tsconfig.json
{
"compilerOptions": {
"paths": {
"@/*": ["src/*"],
"/@/views/*": ["src/views/*"]
}
}
}
import PageOne from '/@/views/PageOne.vue'

More standardized props and emits

stay vue3 in , The parent-child component transfers values props and emits The writing method is more standardized ( More uniform naming ), Embodied in :

  1. v-model The change of
<template>
<child-component v-model:value="myValue"></child-component>
</template>

v-model:value Equate to props:'value' and emits('update:value')

  1. You need to specify the emits

For ease of management , It is suggested that emits Define all of the emit

 export default {
emits: ['update:value', 'otherEmit'],
setup(props, { emit }) {
emit('update:value')
emit('otherEmit')
},
}

track attrs and slots

I thought I could pass watch() Function directly watch(()=>attrs.xxx), It turns out that it can't . There are some on the official website , At first, I didn't pay attention to it :

attrs and slots It's a state object , They are always updated as the component itself updates . This means that you should avoid deconstructing them , And always with attrs.x or slots.x Method reference of property. Please note that , And props Different ,attrs and slots It's nonresponsive . If you're going to base it on attrs or slots Change application side effects , Then it should be in onUpdated Do this in the lifecycle hook .

So respond to it attrs and slots, Need :

import { onUpdated, reactive, watch, watchEffect } from 'vue'
export default {
setup(props, { attrs }) {
function _handleAttrsChange() {
console.log('attrs===')
console.log(attrs)
}
onUpdated(() => {
_handleAttrsChange()
})
// props and data It can be used normally. watch function
watchEffect(() => {
console.log('propsXxx===')
console.log(props.xxx)
})
const state = reactive({ count: 0 })
watch(() => state.count, (now, old) => {
//
})
},
}

VueRouter Do not use directly containing props The components of

I have an address list AddressList, Need to pass through props Receive parent parameters :

// router.js
export default {
name: 'AddressList',
props: {
propName: String,
},
}

By calling the component , No problem . But the configuration is vue-router An error will be reported :

export default {
routes: [
{
path: 'address_list',
component: () => import( 'AddressList.vue'),
},
],
}
TypeError: Cannot add property __props, object is not extensible

Since you can't directly treat a component as route Use , Well, just call it on other pages

// router.js
export default {
routes: [
{
path: 'address_list',
component: () => import( 'Page.vue'),
meta: { component: 'AddressList' },
},
],
}
<!--Page.vue-->
<template>
<component :is="component" />
</template>
<script lang="ts">
import AddressList from '/@/views/AddressList.vue'
import { defineComponent } from 'vue'
export default defineComponent({
name: 'Page',
components: { AddressList },
computed: {
component () {
return this.$route.meta.component
},
},
})
</script>

Related articles

  1. A great one Vue3 Study list
  2. Let you 30 Minute quick grasp vue 3
  3. Start with an article Vue3 In the new API

Last

Official account : Front end development blog , reply 1024, Get the front-end advanced information

版权声明
本文为[Front end development blog]所创,转载请带上原文链接,感谢

  1. [front end -- JavaScript] knowledge point (IV) -- memory leakage in the project (I)
  2. This mechanism in JS
  3. Vue 3.0 source code learning 1 --- rendering process of components
  4. Learning the realization of canvas and simple drawing
  5. gin里获取http请求过来的参数
  6. vue3的新特性
  7. Get the parameters from HTTP request in gin
  8. New features of vue3
  9. vue-cli 引入腾讯地图(最新 api,rocketmq原理面试
  10. Vue 学习笔记(3,免费Java高级工程师学习资源
  11. Vue 学习笔记(2,Java编程视频教程
  12. Vue cli introduces Tencent maps (the latest API, rocketmq)
  13. Vue learning notes (3, free Java senior engineer learning resources)
  14. Vue learning notes (2, Java programming video tutorial)
  15. 【Vue】—props属性
  16. 【Vue】—创建组件
  17. [Vue] - props attribute
  18. [Vue] - create component
  19. 浅谈vue响应式原理及发布订阅模式和观察者模式
  20. On Vue responsive principle, publish subscribe mode and observer mode
  21. 浅谈vue响应式原理及发布订阅模式和观察者模式
  22. On Vue responsive principle, publish subscribe mode and observer mode
  23. Xiaobai can understand it. It only takes 4 steps to solve the problem of Vue keep alive cache component
  24. Publish, subscribe and observer of design patterns
  25. Summary of common content added in ES6 + (II)
  26. No.8 Vue element admin learning (III) vuex learning and login method analysis
  27. Write a mini webpack project construction tool
  28. Shopping cart (front-end static page preparation)
  29. Introduction to the fluent platform
  30. Webpack5 cache
  31. The difference between drop-down box select option and datalist
  32. CSS review (III)
  33. Node.js学习笔记【七】
  34. Node.js learning notes [VII]
  35. Vue Router根据后台数据加载不同的组件(思考-&gt;实现-&gt;不止于实现)
  36. Vue router loads different components according to background data (thinking - & gt; Implementation - & gt; (more than implementation)
  37. 【JQuery框架,Java编程教程视频下载
  38. [jQuery framework, Java programming tutorial video download
  39. Vue Router根据后台数据加载不同的组件(思考-&gt;实现-&gt;不止于实现)
  40. Vue router loads different components according to background data (thinking - & gt; Implementation - & gt; (more than implementation)
  41. 【Vue,阿里P8大佬亲自教你
  42. 【Vue基础知识总结 5,字节跳动算法工程师面试经验
  43. [Vue, Ali P8 teaches you personally
  44. [Vue basic knowledge summary 5. Interview experience of byte beating Algorithm Engineer
  45. 【问题记录】- 谷歌浏览器 Html生成PDF
  46. [problem record] - PDF generated by Google browser HTML
  47. 【问题记录】- 谷歌浏览器 Html生成PDF
  48. [problem record] - PDF generated by Google browser HTML
  49. 【JavaScript】查漏补缺 —数组中reduce()方法
  50. [JavaScript] leak checking and defect filling - reduce() method in array
  51. 【重识 HTML (3),350道Java面试真题分享
  52. 【重识 HTML (2),Java并发编程必会的多线程你竟然还不会
  53. 【重识 HTML (1),二本Java小菜鸟4面字节跳动被秒成渣渣
  54. [re recognize HTML (3) and share 350 real Java interview questions
  55. [re recognize HTML (2). Multithreading is a must for Java Concurrent Programming. How dare you not
  56. [re recognize HTML (1), two Java rookies' 4-sided bytes beat and become slag in seconds
  57. 【重识 HTML ,nginx面试题阿里
  58. 【重识 HTML (4),ELK原来这么简单
  59. [re recognize HTML, nginx interview questions]
  60. [re recognize HTML (4). Elk is so simple