创建项目
基础语法
定义data
- script标签上lang="ts"
- 定义一个类型
type或者接口interface来约束data - 可以使用
ref或者toRefs来定义响应式数据 - 使用
ref在setup读取的时候需要获取xxx.value,但在template中不需要 - 使用
reactive时，可以用toRefs解构导出，在template就可以直接使用了
<script lang="ts"> import { defineComponent, reactive, ref, toRefs } from 'vue'; type Todo = { id: number, name: string, completed: boolean } export default defineComponent({ const data = reactive({ todoList: [] as Todo[] }) const count = ref(0); console.log(count.value) return { ...toRefs(data) } }) </script>
定义props
props需要使用PropType泛型来约束
<script lang="ts"> import { defineComponent, PropType} from 'vue'; interface UserInfo = { id: number, name: string, age: number } export default defineComponent({ props: { userInfo: { type: Object as PropType<UserInfo>, // 泛型类型 required: true } }, }) </script>
定义methods
<script lang="ts"> import { defineComponent, reactive, ref, toRefs } from 'vue'; type Todo = { id: number, name: string, completed: boolean } export default defineComponent({ const data = reactive({ todoList: [] as Todo[] }) // 约束输入和输出类型 const newTodo = (name: string):Todo => { return { id: this.items.length + 1, name, completed: false }; } const addTodo = (todo: Todo): void => { data.todoList.push(todo) } return { ...toRefs(data), newTodo, addTodo } }) </script>
vue-router
createRouter创建router实例router的模式分为：createWebHistory-- history模式createWebHashHistory-- hash模式routes的约束类型是RouteRecordRaw
import { createRouter, createWebHistory, RouteRecordRaw } from 'vue-router';
import Home from '../views/Home.vue';
const routes: Array< RouteRecordRaw > = [
{
path: '/',
name: 'Home',
component: Home,
},
{
path: '/about',
name: 'About',
component: () => import(/* webpackChunkName: "about" */ '../views/About.vue')
}
];
const router = createRouter({
history: createWebHistory(process.env.BASE_URL),
routes
});
export default router;
扩展路由额外属性
在实际项目开发中，常常会遇到这么一个场景，某一个路由是不需要渲染到侧边栏导航上的，此时我们可以给该路由添加一个hidden属性来实现。
在ts的强类型约束下，添加额外属性就会报错，那么我们就需要扩展RouteRecordRaw类型
// 联合类型 type RouteConfig = RouteRecordRaw & {hidden?: boolean}; //hidden 是可选属性 const routes: Array<RouteConfig> = [ { path: '/', name: 'Home', component: Home, hidden: true, meta: { permission: true, icon: '' } } ];
在setup中使用
需要导入useRouter创建一个router实例
<script lang="ts"> import { useRouter } from 'vue-router'; import { defineComponent } from 'vue'; export default defineComponent({ setup () { const router = useRouter(); goRoute(path) { router.push({path}) } } }) </script>
vuex
使用this.$store
import { createStore } from 'vuex';
export type State = {
count: number
}
export default createStore({
state: {
count: 0
}
});
需要创建一个声明文件vuex.d.ts
// vuex.d.ts import {ComponentCustomProperties} from 'vue'; import {Store} from 'vuex'; import {State} from './store' declare module '@vue/runtime-core' { interface ComponentCustomProperties { $store: Store<State> } }
在setup中使用
-
定义InjecktionKey -
在安装插件时传入key -
在使用useStore时传入
import { InjectionKey } from 'vue';
import { createStore, Store } from 'vuex';
export type State = {
count: number
}
// 创建一个injectionKey
export const key: InjectionKey<Store<State>> = Symbol('key');
// main.ts import store, { key } from './store'; app.use(store, key);
<script lang="ts"> import { useStore } from 'vuex'; import { key } from '@/store'; export default defineComponent({ setup () { const store = useStore(key); const count = computed(() => store.state.count); return { count } } }) </script>
模块
新增一个todo模块。导入的模块，需要是一个vuex中的interface Module的对象,接收两个泛型约束，第一个是该模块类型，第二个是根模块类型
// modules/todo.ts import { Module } from 'vuex'; import { State } from '../index.ts'; type Todo = { id: number, name: string, completed: boolean } const initialState = { todos: [] as Todo[] }; export type TodoState = typeof initialState; export default { namespaced: true, state: initialState, mutations: { addTodo (state, payload: Todo) { state.todos.push(payload); } } } as Module<TodoState, State>; //Module<S, R> S 该模块类型 R根模块类型
// index.ts export type State = { count: number, todo?: TodoState // 这里必须是可选，不然state会报错 } export default createStore({ state: { count: 0 } modules: { todo } });
setup () { console.log(store.state.todo?.todos); }
elementPlus
yarn add element-plus
完整引入
import { createApp } from 'vue'
import ElementPlus from 'element-plus';import 'element-plus/lib/theme-chalk/index.css';import App from './App.vue';
import 'dayjs/locale/zh-cn'
import locale from 'element-plus/lib/locale/lang/zh-cn'
const app = createApp(App)
app.use(ElementPlus, { size: 'small', zIndex: 3000, locale })
app.mount('#app')
按需加载
需要安装babel-plugin-component插件
yarn add babel-plugin-component -D // babel.config.js plugins: [ [ 'component', { libraryName: 'element-plus', styleLibraryName: 'theme-chalk' } ] ]
import 'element-plus/lib/theme-chalk/index.css'; import 'dayjs/locale/zh-cn'; import locale from 'element-plus/lib/locale'; import lang from 'element-plus/lib/locale/lang/zh-cn'; import { ElAside, ElButton, ElButtonGroup, } from 'element-plus'; const components: any[] = [ ElAside, ElButton, ElButtonGroup, ]; const plugins:any[] = [ ElLoading, ElMessage, ElMessageBox, ElNotification ]; const element = (app: any):any => { // 国际化 locale.use(lang); // 全局配置 app.config.globalProperties.$ELEMENT = { size: 'small' }; components.forEach(component => { app.component(component.name, component); }); plugins.forEach(plugin => { app.use(plugin); }); }; export default element;
// main.ts import element from './plugin/elemment' const app = createApp(App); element(app);
axios
axios的安装使用和vue2上没有什么大的区别，如果需要做一些扩展属性，还是需要声明一个新的类型
type Config = AxiosRequestConfig & {successNotice? : boolean, errorNotice? : boolean}
import axios, { AxiosResponse, AxiosRequestConfig } from 'axios';
import { ElMessage } from 'element-plus';
const instance = axios.create({
baseURL: process.env.VUE_APP_API_BASE_URL || '',
timeout: 120 * 1000,
withCredentials: true
});
// 错误处理
const err = (error) => {
if (error.message.includes('timeout')) {
ElMessage({
message: '请求超时，请刷新网页重试',
type: 'error'
});
}
if (error.response) {
const data = error.response.data;
if (error.response.status === 403) {
ElMessage({
message: 'Forbidden',
type: 'error'
});
}
if (error.response.status === 401) {
ElMessage({
message: 'Unauthorized',
type: 'error'
});
}
}
return Promise.reject(error);
};
type Config = AxiosRequestConfig & {successNotice? : boolean, errorNotice? : boolean}
// 请求拦截
instance.interceptors.request.use((config: Config) => {
config.headers['Access-Token'] = localStorage.getItem('token') || '';
return config;
}, err);
// 响应拦截
instance.interceptors.response.use((response: AxiosResponse) => {
const config: Config = response.config;
const code = Number(response.data.status);
if (code === 200) {
if (config && config.successNotice) {
ElMessage({
message: response.data.msg,
type: 'success'
});
}
return response.data;
} else {
let errCode = [402, 403];
if (errCode.includes(response.data.code)) {
ElMessage({
message: response.data.msg,
type: 'warning'
});
}
}
}, err);
export default instance;
setup script
官方提供了一个实验性的写法，直接在script里面写setup的内容，即：setup script。
之前我们写组件是这样的
<template> <div> {{count}} <ImgReview></ImgReview > </div> </template> <script lang="ts"> import { ref, defineComponent } from "vue"; import ImgReview from "./components/ImgReview.vue"; export default defineComponent({ components: { ImgReview, }, setup() { const count = ref(0); return { count }; } }); </script>
启用setup script后：在script上加上setup
<template> <div> {{count}} <ImgReview></ImgReview> </div> </template> <script lang="ts" setup> import { ref } from "vue"; import ImgReview from "./components/ImgReview.vue"; const count = ref(0); </script>
是不是看起来简洁了很多，组件直接导入就行了，不用注册组件，数据定义了就可以用。其实我们可以简单的理解为script包括的内容就是setup中的，并做了return
导出方法
<script lang="ts" setup> const handleClick = (type: string) => { console.log(type); } </script>
定义props
使用props需要用到defineProps来定义，具体用法跟之前的props写法类似：
基础用法
<script lang="ts" setup> import { defineProps } from "vue"; const props = defineProps(['userInfo', 'gameId']); </script>
构造函数进行检查 给props定义类型：
const props = defineProps({ gameId: Number, userInfo: { type: Object, required: true } });
使用类型注解进行检查
defineProps<{
name: string
phoneNumber: number
userInfo: object
tags: string[]
}>()
可以先定义好类型：
interface UserInfo { id: number, name: string, age: number } defineProps<{ name: string userInfo: UserInfo }>()
defineEmit
<script lang="ts" setup> import { defineEmit } from 'vue'; // expects emits options const emit = defineEmit(['kk', 'up']); const handleClick = () => { emit('kk', '点了我'); }; </script>
<Comp @kk="handleClick"/> <script lang="ts" setup> const handleClick = (data) => { console.log(data) } </script>
获取上下文
在标准组件写法里，setup 函数默认支持两个入参：
| 参数 | 类型 | 含义 |
| props | object | 由父组件传递下来的数据 |
| context | object | 组件的执行上下文 |
在setup script 中使用useContext获取上下文：
<script lang="ts" setup> import { useContext } from 'vue' const { slots, attrs } = useContext(); </script>
获取到的slots, attrs跟setup里面的是一样的。
关于本文
作者：FinGet
https://juejin.cn/post/6980267119933931551