[Vue warn]: Property or method "evening" is not defined on the instance but referenced during render. Make sure that this property is reactive, either in the data option, or for class-based components, by initializing the property.
<h2>{{ greetX('evening') }}</h2>
是因为调用函数时，传参错误，参数应该加引号 'evening'；
註冊全局組件 1.新增Users.vue <template > <div id="users"> <ol> <!-- vue 遍歷需要key屬性綁定--> <li v-for="(va
App.vue <template> <div id="app"> <Header/> <!--使用組件 並傳遞當前組件值 --> <Users :users="users" :username=
Header.vue <template > <div class="Header"> <h1>{{title}}</h1> </div> </template> <script> //js
scoped的作用：使嵌套的樣式引用不影響當前的vue App.vue <template> <div id="app"> <h1>APP.VUE</h1> <!--使用組件--> <Users/>