How to introduce and use Pinia repository in Vue3

yarn add pinia
# 或者使用 npm
npm install pinia

import { createApp } from 'vue'
import App from './App.vue'
 
const app=createApp(App)
import { createPinia } from 'pinia' //引入pinia
app.use(createPinia())
 
app.mount('#app')

import { defineStore } from 'pinia' //引入pinia
 
//这里官网是单独导出  是可以写成默认导出的  官方的解释为大家一起约定仓库用use打头的单词 固定统一小仓库的名字不易混乱
export const useCar=defineStore("test",{ 
    state: () =>{
        return  ({
            msg:"这是pinia",
            name:"小小",
            age:18
            }) //为了避免出错，返回的值用()包起来
    } 
})

<template>
    <h2>{{store.msg}}{{store.name}}{{store.age}}</h2>
    <button @click="modify">修改store.name</button>
</template>
 
<script>
import { defineComponent, ref } from &#39;vue&#39;;
import {
  reactive,
  toRefs,
  onMounted,
  onActivated
} from "vue";
import {useCar} from "../store/index.js" //将之前配置的pinia文件夹中的index.js文件引入
export default defineComponent({
  let store=useCar() //接收
  setup() {
    const state = reactive({
      testMsg: "原始值",
    });
    onMounted(async () => {});
    onActivated(() => {})
    const methods = {
        modify(){
             store.name = state.testMsg //修改pinia里面的数据
             console.log(store.name)
        }
    };
    return {
      ...toRefs(state),
      ...methods,
    };
  }
})
</script>

<template>
    <h2>{{store.msg}}{{store.name}}{{store.age}}</h2>
    <button @click="reset">重置store.name</button>
</template>
 
<script>
import { defineComponent, ref } from &#39;vue&#39;;
import {
  reactive,
  toRefs,
  onMounted,
  onActivated
} from "vue";
import {useCar} from "../store/index.js" //将之前配置的pinia文件夹中的index.js文件引入
export default defineComponent({
  let store=useCar() //接收
  setup() {
    const state = reactive({
      testMsg: "原始值",
    });
    onMounted(async () => {});
    onActivated(() => {})
    const methods = {
        reset(){
             store.$reset() //重置pinia里面的数据
             console.log(store.name)
        }
    };
    return {
      ...toRefs(state),
      ...methods,
    };
  }
})
</script>

<template>
    <h2>{{store.msg}}{{store.name}}{{store.age}}</h2>
    <button @click="modify">修改store.name</button>
    <button @click="reset">重置store.name</button>
    <button @click="allModify">群体修改store.name</button>
</template>
 
<script>
import { defineComponent, ref } from &#39;vue&#39;;
import {
  reactive,
  toRefs,
  onMounted,
  onActivated
} from "vue";
import {useCar} from "../store/index.js" //将之前配置的pinia文件夹中的index.js文件引入
export default defineComponent({
  let store=useCar() //接收
  setup() {
    const state = reactive({
      testMsg: "原始值",
    });
    onMounted(async () => {});
    onActivated(() => {})
    const methods = {
        modify(){
             store.name = state.testMsg //修改pinia里面的数据
             console.log(store.name)
        },
        reset(){
             store.$reset() //重置pinia里面的数据
             console.log(store.name)
        },
        allModify(){
             store.$patch({
              name:"花花",
              age:20,
            })
        }
    };
    return {
      ...toRefs(state),
      ...methods,
    };
  }
})
</script>

//可以通过 store 的 $subscribe() 方法查看状态及其变化,通过patch修改状态时就会触发一次
store.$subscribe((mutation, state) => { 
  // 每当它发生变化时，将整个状态持久化到本地存储
  localStorage.setItem('hello', JSON.stringify(state))
})

//store/index.js文件
export const useStore = defineStore('main', {
  state: () => ({
    counter: 0,
  }),
  getters: {
    doubleCount: (state) => state.counter * 2,
  },
})
 
//组件中直接使用:  <p>Double count is {{ store.doubleCount }}</p>

export const useStore = defineStore('main', {
  state: () => ({
    counter: 0,
  }),
  actions: {
    increment() {
      this.counter++//1.有this
    },
    randomizeCounter(state) {//2.有参数   想用哪个用哪个
      state.counter = Math.round(100 * Math.random())
    },
    randomizeCounter(state) {
        //异步函数.接口成功赋值
     ajax.hplBaseApi("app/productSelection/categoryRows", {}, "post").then((res) => {
        state.counter = res.data.length
     });
    }
  },
})
 
//组件中的使用:
  setup() {
    const store = useStore()
    store.increment()
    store.randomizeCounter()
  }