Vue3新特性
- ES5：defineProperty：劫持 ----> ES6：Proxy：拦截
- defineProperty：无法监听动态新增属性，需要$set
- Proxy：解决之前监听数组的漏洞，如：可直接push、自动追踪深层嵌套对象变化、内存占用显著降低、渲染性能优化
- 包体积更小（按需打包）
- 虚拟dom
- TypeScript
- 生命周期
- Fragment、Teleport、Suspense
vue3的生命周期
| vue2.x |
vue3.x |
| beforeCreated |
Not needed* |
created |
Not needed* |
beforeMount |
onBeforeMount |
mounted |
onMounted |
beforeUpdate |
onBeforeUpdate |
updated |
onUpdated |
beforeUnmount |
onBeforeUnmount |
unmounted |
onUnmounted |
errorCaptured |
onErrorCaptured |
renderTracked |
onRenderTracked |
renderTriggered |
onRenderTriggered |
activated |
onActivated |
deactivated |
onDeactivated |