import Vue from "vue"
import Vuex from "vuex"
Vue.use(Vuex)
const store = new Vuex.Store({
  state: {
    list: [],
  },
  getters: {},
  mutations: {
    setList(state, list) {
      state.list = list;
    },
    addItem(state, item) {
      state.list.push(item);
    },
    updateItem(state, payload) {
      Vue.set(state.list, payload.index, payload.data);
    },
    deleteItem(state, lt) {
      let newIds = lt.map((item) => item.aid);
      state.list = state.list.filter((item) => newIds.includes(item.aid));
    },
  },
  actions: {}
})
export default store;

組件中維護數組，進行判斷

對象數組數據格式

[
  { "aid": "1", "aname": "111", "tobid": "1" }
  { "aid": "2", "aname": "ddd", "tobid": "2" }
]

組件中判斷

新建的時候進行判斷that.list.length == 0 || that.list == null，直接set賦值即可
如果不為0，說明已經初始化并賦值，遍歷當前數組（本文中數據來自后端）
id不存在（舊數組沒有而新數組有），則調用add添加
id存在需要判斷這個對象是否完全相同，不完全相同則調用update
最后調用delete，store中直接使用filter過濾掉新數組中有而舊數組沒有的對象（delete的邏輯可以單獨存在，不與更新一起）

自行修改使用：大更新需要add和delete，局部更新只有update

例如舊數組是【1，2】，新數組是【2，3】，經過第二步之后，舊數據變?yōu)椤?，2，3】，但【1】是需要刪除的

<template>
  <div class="form-all">
    <el-button @click="getList()">getList</el-button>
    <el-button @click="clearStorage()">clear Local Storage</el-button>
    <div v-for="(item) in list" :key="item.aid">{{ item }}</div>
  </div>
</template>
<script>
import { mapState, mapMutations } from "vuex";
export default {
  name: "demo",
  data() {
    return {
      lit: [],
    };
  },
  components: {},
  computed: {
    ...mapState(["list"]),
  },
  methods: {
    ...mapMutations(["setList", "addItem", "updateItem", "deleteItem"]),
    clearStorage() {
      // localStorage.setItem("list", []);
      localStorage.removeItem('list');  
    },
    getList() {
      console.log(this.list.length);
      let that = this;
      this.axios
        .get('/abc/onetooneAnnote')
        .then((response) => {
          //返回結果
          let lt = response.data;
          this.setStore(lt);
        })
        .catch((error) => {
          console.log(error)
        })
    },
    setStore(lt) {
      let that = this;
      if (that.list.length == 0) {
        //初始化
        this.setList(lt);
      } else {
        let lit = that.list;
        lt.forEach((newItem, i) => {
          const index = lit.findIndex((litem) => litem.aid === newItem.aid);
          if (index == -1) {
            // 添加
            this.addItem(newItem);
          } else {
            const oldItem = lit[index];
            if (JSON.stringify(oldItem) != JSON.stringify(newItem)) {
              // 更新
              let payload = {
                data: newItem,
                index: index,
              }
              this.updateItem(payload);
            }
          }
        })
        //刪除
        this.deleteItem(lt);
      }
    },
  },
  mounted() {
  },
  created() {},
  destroyed() {},
  watch: {},
}
</script>
<style scoped>
</style>
<style></style>

存入localstorage并設置定時刪除

不刷新頁面，使用的vuex內的值，刷新頁面才會重新從localstorage中獲取

自定義實現

使用subscribe監(jiān)聽指定的mutation方法，對應方法調用則更新localstorage
實現函數setItemWithExpiry，將時間作為變量和數據整編成一個對象，存入localStorage，在subscribe時調用此函數

import Vue from "vue"
import Vuex from "vuex"
Vue.use(Vuex)
// 將數據存儲到LocalStorage并設置過期時間（毫秒）
function setItemWithExpiry(key, value, ttl) {
  const item = {
    value: value,
    expiry: new Date().getTime() + ttl,
  };
  localStorage.setItem(key, JSON.stringify(item));
}
const store = new Vuex.Store({
  state: {
    list: JSON.parse(localStorage.getItem("list")).value || [],
  },
  getters: {},
  mutations: {
    setList(state, list) {
      state.list = list;
    },
    addItem(state, item) {
      state.list.push(item);
    },
    updateItem(state, payload) {
      Vue.set(state.list, payload.index, payload.data);
    },
    deleteItem(state, lt) {
      let newIds = lt.map((item) => item.aid);
      state.list = state.list.filter((item) => newIds.includes(item.aid));
    },
  },
  actions: {}
})
// 監(jiān)聽訂閱
store.subscribe((mutation, state) => {
  if (['setList', 'addItem', 'updateItem', 'deleteItem'].includes(mutation.type)) {
    // 不設置定時刪除
    // localStorage.setItem('list', JSON.stringify(state.list));
    // 使用定時刪除
    setItemWithExpiry("list", state.list, 10 * 1000);
  }
});
export default store;

其中獲取vuex的值，如果每次都想直接從localstorage中讀取，可以使用store的getters屬性

  getters: {
    getList: (state) => {
      return state.list;
    },
  },

組件中使用

<div v-for="(item) in getList" :key="item.aid">{{ item }}</div>
import { mapGetters } from "vuex";
  computed: {
    ...mapGetters(['getList']),
  },

使用storage-timing插件

官方github地址：https://github.com/xxwwp/StorageTiming/blob/main/docs/zh.md

調用定時刪除

設置定時器，可以在App.vue中全局設置
checkExpiry可以遍歷全部localstorage，也可以只關注某幾個變量

<template>
  ...
</template>
<script>
export default {
  data() {
    return {
      timer: "",
    }
  },
  components: {},
  methods: {
    getItemWithExpiry(key) {
      const itemStr = localStorage.getItem(key);
      if (!itemStr) {
        return null;
      }
      const item = JSON.parse(itemStr);
      const currentTime = new Date().getTime();
      if (currentTime > item.expiry) {
        // 如果數據已經過期，刪除它
        localStorage.removeItem(key);
        return null;
      }
      return item.value;
    },
    // 檢查LocalStorage中的數據是否過期
    checkExpiry() {
      this.getItemWithExpiry("list");
      // for (let i = 0; i < localStorage.length; i++) {
      //   const key = localStorage.key(i);
      //   getItemWithExpiry(key);
      // }
    },
    startCheck(){
      let that = this;
      this.timer = setInterval(() => { //開啟定時器
        console.log("check localstorage");
        that.checkExpiry()
      }, 1000)
    }
  },
  mounted() {
    this.startCheck();
  },
  beforeDestroy(){
    clearInterval(this.timer)//組件銷毀之前清掉timer
  },
  computed: {},
  created() {
  },
}
</script>
<style scoped></style>
<style></style>