Vue项目中最新用到的一些实用小技巧

.avatar
 display: flex;
 justify-content: center;
 align-items: center;

.avatar-img
 padding 20px
 border solid 1px #ccc
 border-radius 5px

<template>
 <div class="avatar">
 <img class="avatar-img" src="/UploadFiles/2021-04-02/avatar.png">

需要注意的是，如果不是通过 import 引入则需要在别名前加上 ~，效果如下：

需求二：要求实现在生产包中直接修改api地址


这个需求，怎么说呢，反正就是需求，就想办法实现吧。


假设有一个 apiConfig.js 文件，用于对 axios 做一些配置，如下：




import axios from 'axios';

axios.defaults.timeout = 10000;
axios.defaults.retry = 3;
axios.defaults.retryDelay = 2000;
axios.defaults.responseType = 'json';
axios.defaults.withCredentials = true;
axios.defaults.headers.post["Content-type"] = "application/json";

// Add a request interceptor
axios.interceptors.request.use(function (config) {
 // Do something before request is sent
 return config;
}, function (error) {
 // Do something with request error
 return Promise.reject(error);
});

// Add a response interceptor
axios.interceptors.response.use(function (response) {
 // Do something with response data
 return response;
}, function (error) {
 // Do something with response error
 return Promise.reject(error);
});

export default axios


在 static 文件夹中增加一个 config.json 文件，用于统一管理所有的 api 地址：




{
 "base": "/api",
 "static": "//static.com/api",
 "news": "//news.com.api"
}


打开 main.js，写入下列代码：




// The Vue build version to load with the `import` command
// (runtime-only or standalone) has been set in webpack.base.conf with an alias.
import Vue from 'vue'
import App from './App'
import router from './router'
import ElementUI from 'element-ui';
import 'element-ui/lib/theme-chalk/index.css';
import axios from 'js/apiConfig'; //import直接引入，不用添加~

Vue.config.productionTip = false;
Vue.use(ElementUI);

/* eslint-disable no-new */
let startApp = function () {
 let randomStamp = new Date().getTime();
 axios.get(`/static/config.json"external nofollow" target="_blank" href="http://element-cn.eleme.io/#/zh-CN/component/menu">ElementUI ，参考了道友的这篇文章，实现如下：


新建一个 Menu.vue 文件，写入如下代码：




<script>
 export default {
 name: "MenuItem",
 props: {
 data: {
 type: Array
 },
 collapse: {
 type: Boolean
 }
 },
 methods: {
 //生成菜单项
 createMenuItem(data, createElement) {
 return data.map(item => {
  if (item.children && item.children.length) {
  return createElement('el-submenu', {props: {index: item.id.toString()}},
  [
  createElement('template', {slot: 'title'}, [
   createElement('i', {class: item.icon}),
   createElement('span', [item.title]),
   ]
  ),
  this.createMenuItem(item.children, createElement) //递归
  ]
  )
  } else {
  return createElement('el-menu-item', {props: {index: item.path}},
  [
  createElement('i', {class: item.icon}),
  createElement('span', {slot: 'title'}, [item.title]),
  ]
  )
  }
 })
 },
 //选中菜单
 onSelect(key, keyPath) {
 console.log(key, keyPath);
 }
 },
 render(createElement) {
 return createElement(
 'el-menu',
 {
  props: {
  backgroundColor: "#545c64",
  textColor: "#fff",
  activeTextColor: "#ffd04b",
  collapse: this.collapse,
  router:true
  },
  class:'el-menu-vertical-demo',
  on: {
  select: this.onSelect
  }
 },
 this.createMenuItem(this.data, createElement)
 )
 }
 }
</script>

<style scoped lang="stylus">
 .el-menu-vertical-demo:not(.el-menu--collapse) {
 width: 200px;
 min-height: 400px;
 }
</style>


这里主要用到两个东西，一个是 render 函数，一个是递归，如果不熟悉 render 函数的道友请点这里。可能有道友会问为什么不用模板，因为······做不到啊"htmlcode">

<template>
 <el-container>
 <el-aside width="auto">
 <Menu :data="menu" :collapse="isCollapsed"></Menu>
 </el-aside>
 <el-container>
 <el-header>
 <el-button type="text" icon="el-icon-d-arrow-left"
   @click="isCollapsed=!isCollapsed"></el-button>
 <h3>MenuName</h3>
 <span>MeFelixWang</span>
 </el-header>
 <el-main>
 <router-view></router-view>
 </el-main>
 </el-container>
 </el-container>
</template>

<script>
 import Menu from '@/components/Menu';

 export default {
 name: 'App',
 data() {
 return {
 menu: [
  {
  title: '导航一',
  id: 1,
  path: '',
  icon: 'el-icon-search',
  children: [
  {
  title: '导航一杠一', id: 2, path: '', icon: '', children: [
   {title: '导航一杠一杠一', id: 4, path: '/test', icon: '', children: []},
   {
   title: '导航一杠一杠二', id: 5, path: '', icon: '', children: [
   {title: '导航一杠一杠二杠一', id: 6, path: '/6', icon: '', children: []},
   {title: '导航一杠一杠二杠二', id: 7, path: '/7', icon: '', children: []},
   ]
   },
  ]
  },
  {title: '导航一杠二', id: 3, path: '/3', icon: '', children: []}
  ]
  },
  {title: '导航二', id: 8, path: '/8', icon: 'el-icon-setting', children: []},
  {title: '导航三', id: 9, path: '/9', icon: 'el-icon-document', children: []},
  {
  title: '导航四', id: 10, path: '', icon: 'el-icon-date', children: [
  {title: '导航四杠一', id: 11, path: '/11', icon: '', children: []},
  {
  title: '导航四杠二', id: 12, path: '', icon: '', children: [
   {title: '导航四杠二杠一', id: 14, path: '/14', icon: '', children: []}
  ]
  },
  {title: '导航四杠三', id: 13, path: '/13', icon: '', children: []},
  ]
  },
 ],
 isCollapsed: false
 }
 },
 methods: {
 handleOpen(key, keyPath) {
 console.log(key, keyPath);
 },
 handleClose(key, keyPath) {
 console.log(key, keyPath);
 }
 },
 components: {
 Menu
 }
 }
</script>

<style lang="stylus">
 *
 margin 0
 padding 0

 html, body, .el-container, .el-aside
 height 100%

 .el-aside
 background-color rgb(84, 92, 100)

 .el-menu
 border-right solid 1px rgb(84, 92, 100)

 .el-header
 display flex
 justify-content space-between
 align-items center
 background-color aliceblue
 .el-button--text
 color: #606266;
 i
 font-weight bold
</style>


效果如下：

需求四：这个 Select 选项是树形结构，一定得是树形结构


树形结构就树形结构吧，不就是样式嘛，改改应该就可以了。




<template>
 <div>
 <el-select v-model="tree" placeholder="请选择活动区域">
 <el-option v-for="(item,index) in options" :key="index" :label="item.label" :value="item.id"
   :style="{paddingLeft:(item.level*10+20)+'px'}" :class="item.level"></el-option>
 </el-select>
 选择的是：{{tree}}
 </div>
</template>

<script>
 export default {
 name: "Home",
 data() {
 return {
 tree: '',
 options: [],
 originData: [
  {
  label: '这是根一', id: 1, children: [
  {label: '这是茎一一', id: 2, children: []},
  {label: '这是茎一二', id: 3, children: []},
  {
  label: '这是茎一三', id: 4, children: [
   {label: '这是叶一三一', id: 6, children: []},
   {label: '这是叶一三二', id: 7, children: []},
  ]
  },
  {label: '这是茎一四', id: 5, children: []},
  ]
  },
  {
  label: '这是根二', id: 8, children: [],
  },
  {
  label: '这是根三', id: 9, children: [
  {label: '这是茎三一', id: 10, children: []},
  {
  label: '这是茎三二', id: 11, children: [
   {label: '这是叶三二一', id: 12, children: []}
  ]
  },
  ],
  },
 ]
 }
 },
 created() {
 this.options = this.decomposeTree(this.originData, 0);
 },
 methods: {
 //分解树形结构
 decomposeTree(array, level) {
 let tmpArr = [];

 (function decompose(arr, lev) {
  for (let i = 0; i < arr.length; i++) {
  let tmpObj = {};
  let item = arr[i];
  item.level = lev;
  tmpObj = Object.assign({}, item);
  tmpArr.push(tmpObj);
  if (item.children) {
  decompose(item.children, lev + 1); //递归
  }
  delete tmpObj.children; //删掉其 children，避免数据过大（不删也可以，也许后面有用呢）
  }

 })(array, level);

 return tmpArr;
 }
 }
 }
</script>

<style scoped lang="stylus">
 .is-sub:before
 content '- '
</style>


因为 option 接收的是一个一维数组，所以通过递归展平树形结构，在展平的时候设置每项的层级，通过层级来设置缩进及前缀符号，效果如下：

之所以这样做，是因为是管理系统，简单有效，没必要因为这一个组件引个新的插件或者自己写一个（以后用得着的除外哈）；也可以用 input 加上 tree 控件来模拟（PS：最终还是引入了一个插件，哈哈"color: #ff0000">最后叨叨

本文是我最近用到的一些小技巧，如果道友们有更好的实现方法，欢迎在评论区留言讨论，文中错误也欢迎指出，共同学习
以上就是这篇文章的全部内容了，希望本文的内容对大家的学习或者工作具有一定的参考学习价值，谢谢大家对的支持。