multipage/src/app/main.js

import Vue from 'vue'
import App from './App.vue'
import router from '@/router'
import store from '@/store'

Vue.config.productionTip = false


router.beforeEach((to, from, next) => {
    if (!to.query.appId) {
        if (from.query.appId) {
            to.query.appId = from.query.appId
        } else {
            to.query.appId = window.location.href.match(/appId=(.*)/)[1]
        }
    }
    next()
})

router.afterEach((to, from) => {

})

new Vue({
    router,
    store,
    render: h => h(App)
}).$mount('#app')