待补充

index.js store

export default new Vuex.Store({
  state: {
    count: 0,
  },
mutations: {
    add(state, step) {
      //第一个形参永远都是state
      //第二个形参是调用此方法时传递的参数
      state.count += step;
      console.log(state.count)
    },
}
actions: {
 addAsync(context, step) {
      setTimeout(() => {
        context.commit("add", step);
      }, 2000);
    },
}
}

组件使用 ==>存入异步的数据到vuex

import { mapActions, mapMutations, mapState } from "vuex";

 computed: {
    ...mapState(["count"]), // 使用
}

 methods: {
    ...mapActions(["getCourseDetail", "getCourseList", "addAsync"]),
    ...mapMutations(["bannersState"]),
    AddAsync() {
      this.addAsync(1);
    },
}

count不要在data里面写了，直接在模板里使用：

<div @click="AddAsync">点击</div>
    {{ count }}