Vue2.js迁移到Vue3.js的API变化，-表示移除
| Vue2.js | Vue3.js |
| new Vue() | createApp() |
| Vue.extend | defineComponent or extends |
| Vue.prototype | app.config.globalProperties |
| Vue.set | - |
| Vue.delete | - |
| Vue.observable | reactive |
| config.keyCodes | - |
| vm.$set | - |
| vm.$delete | - |
| vm.$on | - |
| vm.$off | - |
| vm.$once | - |
| vm.$children | - |
| vm.$listeners | - |
| hook:x | - |
| vm.$scopedSlots | - |
| vm.$slots | now exposes functions |
| $attrs | now includes class and style |
| data | must be a function in all cases |
| data | from mixin or extension is now shallow merged |
| beforeDestroy | beforeUnmount |
| destroyed | unmounted |
| v-on | no longer supports keyCode modifiers |
| - | watching an array no longer triggers on mutation unless deep |
| - | Custom directive hook names changed |
| - | No longer removes attribute if binding value is boolean false |
| - | No longer special case enumerated attributes |
<transition-group> |
no longer renders a root element by default |
| - | Async component API changed (now requires defineAsyncComponent) |
| - | Functional component API changed (now must be plain functions) |
| - | Component v-model reworked |
| - | Render function API changed |
| - | Filters removed (this option affects only runtime filter APIs) |
| - | is usage is now restricted to <component> only |
| v-bind.sync | replaced by v-model with arguments |
| v-bind.prop | modifier removed |
| v-bind=“object” | is now order sensitive |
| v-on.native | modifier removed |
| - | ref in v-for (compiler support) |
<template> |
with no special directives now renders as native element |
| - | filters (compiler support) |
参考
https://v3-migration.vuejs.org/migration-build.html#fully-compatible
