浅析集中式状态管理Vuex的使用方法

<template>
  <div>
    <h3>当前和为：{{sum}}</h3>
    <h3>当前和为：放大10倍：{{bigSum}}</h3>
    <h3>我在{{school}},学习{{subject}}</h3>
    <h3>下方组件的总人数{{personList.length}}</h3>

    <select v-model.number="num">
      <option value="1">1</option>
      <option value="2">2</option>
      <option value="3">3</option>
    </select>
    <button @click="increment(num)">＋</button>
    <button @click="decrement(num)">-</button>
    <button @click="incrementOdd(num)">奇数＋</button>
    <button @click="incrementWait(num)">500ms后再＋</button>
  </div>
</template>
<script>
// 引入mapState等
import { mapState, mapGetters, mapMutations, mapActions } from "vuex";
export default {
  name: "Count",
  data() {
    return {
      num: 1 // 用户选择的数字
    };
  },
  computed: {
    // 使用mapState生成计算属性，从state种读取数据(...mapstate()的意思是将其内的对象全部展开的计算属性里面)
    // ...mapState({ sum: "sum", school: "school", subject: "subject" }), // 对象写法
    ...mapState(["sum", "school", "subject", "personList"]), // 数组写法
    // 使用mapGetters生成计算属性，从getters种读取数据
    // ...mapGetters(["bigSum"]), // 数组写法
    ...mapGetters({ bigSum: "bigSum" }) // 数组写法
  },
  methods: {
    // 借助mapMutations生成对应的方法，方法种会调用相应的commit去联系mutations
    ...mapMutations({ increment: "JIA", decrement: "JIAN" }), // 对象式
    ...mapActions({ incrementOdd: "jiaodd", incrementWait: "jiaWait" }) //数组式
    // ...mapActions(["jiaodd", "jiaWait"]) //数组式简写
  },
  mounted() {
  }
};
</script>
<style>
button {
  margin-left: 5px;
}
</style>

<template>
  <div>
    <h3>人员列表</h3>
    <h3>Count组件的求和为{{sum}}</h3>
    <input type="text" placehodler="请输入名字" v-model="name">
    <button @click="add">添加</button>
    <ul>
      <li v-for="p in personList" :key="p.id">{{p.name}}</li>
    </ul>
  </div>
</template>
<script>
import { nanoid } from "nanoid";
export default {
  name: "Person",
  data() {
    return {
      name: ""
    };
  },
  computed: {
    personList() {
      return this.$store.state.personList;
    },
    sum() {
      return this.$store.state.sum;
    }
  },
  methods: {
    add() {
      const personObj = { id: nanoid(), name: this.name };
      this.$store.commit("ADD_PERSON", personObj);
      this.name = "";
    }
  }
};
</script>

<template>
  <div class="container">
    <Count></Count>
    <Person/>
  </div>
</template>

<script>
import Count from "./components/Count";
import Person from "./components/Person";
export default {
  name: "App",
  components: { Count, Person }
};
</script>

// 创建VUex种的store核心
import Vue from 'vue'
// 引入Vuex
import Vuex from 'vuex'
// 使用vuex插件
Vue.use(Vuex)
// 准备actions——用于组件内的动作响应
const actions = {
    // 奇数加法
    jiaodd(context, value) {
        if (context.state.sum % 2) {
            context.commit('JIA', value)
        }
    },
    // 延迟加
    jiaWait(context, value) {
        setTimeout(() => {
            context.commit("JIA", value)
        }, 500);
    },
}
// 准备mutations——用于数据操作
const mutations = {
    JIA(state, value) {
        state.sum += value
    },
    JIAN(state, value) {
        state.sum -= value
    },
    ADD_PERSON(state, value) {
        console.log('mustations种的ADD_PERSON被调用',state.personList);
        state.personList.unshift(value)
    }
}
// 准备state——用于数据的储存
const state = {
    sum: 0, // 当前和
    school: '山鱼小学',
    subject: '前端',
    personList:[{id:'001',name:'张三'}]
}
// 用于加工state种的数据
const getters = {
    bigSum(state) {
        return state.sum * 10
    }
}
// 创建store并且暴露store
export default new Vuex.Store({
    // actions: actions,// 前后名称一样所以可以触发简写模式
    actions,
    mutations,
    state,
    getters
});

computed: {
    // 使用mapState生成计算属性，从state种读取数据(...mapstate({})的意思是将其内的对象全部展开的计算属性里面)
    ...mapState({ sum: "sum", school: "school", subject: "subject" }), // 对象写法
        
    // ...mapState(["sum", "school", "subject"]), // 数组写法
  }

computed: {
    // 使用mapGetters生成计算属性，从getters种读取数据
    ...mapGetters({bigSum："bigSum"})
    ...mapGetters(["bigSum"])
  }

methods: {
    // 借助mapMutations生成对应的方法，方法种会调用相应的commit去联系mutations
    ...mapMutations({ increment: "JIA", decrement: "JIAN" }), // 对象式
    // ...mapMutations(["JIA", "JIAN"]), // 数组式(button的名字和vuex里面的名字必须统一)
  },

  methods: {
     // 借助mapActions生成对应的方法，方法种会调用相应的dispath去联系actions
    ...mapActions({ incrementOdd: "jiaodd", incrementWait: "jiaWait" }), //对象式
    // ...mapActions(["jiaodd", "jiaWait"]) //数组式
  },