結合sessionStorage解決vuex頁面刷新數據丟失的問題

將需要保存在vuex中的數據同時保存在sessionStorage中即可：

import Vue from 'vue';
import Vuex from 'vuex';

Vue.use(Vuex);

const state = {
    count: 0,
};

const mutations = {
    increaseCount(state, num) {
        state.count = state.count + num;
        sessionStorage.setItem('count', JSON.stringify(state.count));
    },
    reduceCount(state, num) {
        state.count = state.count - num;
        sessionStorage.setItem('count', JSON.stringify(state.count));
    }
}
// 頁面刷新時，會從sessionStorage中重新讀取並賦值
for(let key in state) {
    sessionStorage.getItem(key) ? state[key] = sessionStorage.getItem(key) : false;
}
export default new Vuex.Store({
    state,
    mutations
})