vue3定义全局变量方法变更及$on废弃(Vue3 global variable definition method change and $on Abandonment)

在vue2中，直接

Vue.prototype.$bus = new Vue()

但是在vue3中，方法改变了（因为$on方法的废弃，需要用到mitt）

const app = createApp(App)
app.config.globalProperties.$bus = new mitt();
app.use(store).use(router).mount('#app')

则使用$bus.emit去提交

然后使用$bus.on 去获取（没有$）

  imageLoad() {
    this.$bus.$emit('itemImageLoad')
  },

      this.$bus.on('itemImageLoad', () => {
        refresh()
      });

参考：https://blog.csdn.net/qq_39179734/article/details/120740618

————————

In vue2, direct

Vue.prototype.$bus = new Vue()

But in vue3, the method is changed (mitt is needed because of the abandonment of the $on method)

const app = createApp(App)
app.config.globalProperties.$bus = new mitt();
app.use(store).use(router).mount('#app')

Use $bus Emit to submit

Then use $bus On to get (no $)

  imageLoad() {
    this.$bus.$emit('itemImageLoad')
  },

      this.$bus.on('itemImageLoad', () => {
        refresh()
      });

参考：https://blog.csdn.net/qq_39179734/article/details/120740618