npm install vuex -d

import Vue from 'vue'
import Vuex from 'vuex'
 
Vue.use(Vuex)
const key = 'user'
const store = new Vuex.Store({
 state () {
  return {
   user: null
  }
 },
 getters: {
  getStorage: function (state) {
   if (!state.user) {
    state.user = JSON.parse(localStorage.getItem(key))
   }
   return state.user
  }
 },
 mutations: {
  $_setStorage (state, value) {
   state.user = value
   localStorage.setItem(key, JSON.stringify(value))
  },
  $_removeStorage (state) {
   state.user = null
   localStorage.removeItem(key)
  }
 }
})
 
export default store

import store from './store/index'
new Vue({
 el: '#app',
 router,
 store, // 引入store
 components: { App },
 template: '<App/>'
})

this.$message({
  message: '登录成功',
  type: 'success'
})
this.$store.commit('$_setStorage', {user: this.loginForm.username})
this.$router.push({name: 'Home'})