安装

npm i pinia

main.ts

import './assets/main.css'

import { createApp } from 'vue'
import App from './App.vue'
import { createPinia } from 'pinia' // 引入Pinia

// 创建一个应用
const app = createApp(App)

const pina = createPinia()
app.use(pina)
// 挂载整个应用到app容器
app.mount('#app')

'src/store'文件夹——Pinia的实际体现

        

count.ts

被命名为count是为了和 src/components/Count.vue对应

import {defineStore} from 'pinia'

// useCountStore对应Count 其他的名字也同理
export const useCountStore = defineStore(

    // 第一个参数：相当于id值
    'count', 

    // 第二个参数：配置对象
    {
        // 真正存储数据的地方
        state() { 
            return {
                sum:1,
                x:'xx',
                y:'yy'
            }
        },

        // 
        actions:{
            increment(v) {
                this.sum += v // this是useCountStore
            }
        }
    }
)

sentence.ts

import {defineStore} from 'pinia'

// useCountStore对应Count 其他的名字也同理
export const useSentenceStore = defineStore(
    // 第一个参数：相当于id值
    ('sentence'), 
    // 第二个参数：配置对象
    {
        state() { // 真正存储数据的地方
            return {
                sentenceList:[
                    {id:'1', title:'11'},
                    {id:'2', title:'22'},
                    {id:'3', title:'33'},

                ]
            }
        }
    }
)

Vue插件的Pinia结果

提前准备的效果

Count.vue

<template>
    <h2>Sum = {{ countStore.sum }}  x = {{ countStore.x }}</h2>

    <select v-model.number="n">
        <option value="1">1</option>
        <option value="2">2</option>
        <option value="3">3</option>
    </select>
    <button @click="add">+</button>
    <button @click="minus">-</button>
</template>

<script setup lang="ts" name="Count">
    import {ref} from "vue";
    import {useCountStore} from '@/store/count'
import type { createIncrementalCompilerHost } from "typescript";

    const countStore = useCountStore()

    let n = ref(0)

    function add() {
        // 第一种修改方式
        // countStore.sum += n.value

        // 第二种修改方式
        // countStore.$patch(
        //     {
        //         sum: 999,
        //         x:'xxxxx',
        //         y:'yyyyy'
        //     }
        // )

        // 第三章修改方式
        // 配合count.ts的action
        countStore.increment(n.value)
    }

    function minus() {
        countStore.sum -= n.value
    }

</script>

sentence.vue

<template>
    <button>get</button>
    <li v-for="sen in sentenceStore.sentenceList" :key="sen.id">{{ sen.title }}</li>
</template>

<script setup lang="ts" name="sentence">
    import {useSentenceStore} from '@/store/sentence'

    const sentenceStore = useSentenceStore()
</script>

App.vue

<template>
    <Count/>
    <br>
    <sentence/>
</template>
  
<script lang="ts" setup name="App">
  import {RouterView, RouterLink} from 'vue-router'
  import Count from './components/Count.vue'
  import sentence from './components/sentence.vue'
</script>

<style scoped>
/* 可以添加一些样式 */
</style>