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<script src="https://unpkg.com/vue@next"></script>
<div id="app">
<p>{{text}}</p>
<input type="text" v-model="text"/>
<!-- v-if 會直接拔除、塞入 DOM-->
<p v-if="message.show">{{message.name}}</p>
<p>Number: {{number}}</p>
<p>Multiple * 5 : {{multipleNumber}}</p>
<p>Object Index: {{indexInObject.index}}</p>
<button @click="add">Add</button>
<button @click="minus">Minus</button>
<button @click="addToReadOnly">AddToReadOnly</button>
<button @click="changeMessageStatus">Show / Hide Message</button>
<br/>
<br/>
<div class="box__wrapper">
<a href="#" @click="displayCountryCode">Click to open / close</a>
<ul :class="['box',{open:isOpen}]">
<!-- v-show 用 css 的方法來控制開關-->
<!-- v-bind:key 可以避免更動時都重新渲染,避免使用 array index 當 key,以免渲染錯誤-->
<!-- v-if 和 v-for 是不能同時使用的,v-if 的優先權高於 v-for-->
<!-- 請先用 js 篩選完資料後,再用 v-for -->
<li
v-for="(country,index) in countryCodes"
:key="country.code"
v-show="country.show"
:class="[country.class,{open:isOpen}]"
>
{{index+1}}. {{country.name}} | {{country.code}}
</li>
</ul>
</div>
</div>
#app {
font-family: Avenir, Helvetica, Arial, sans-serif;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
text-align: center;
color: #2c3e50;
margin-top: 60px;
}
.box{
padding:12px;
background-color: rgb(218, 214, 214);
transition: height 0.4s;
height:0px
}
.box.open{
height:120px;
}
.box > li{
display: none;
justify-content: center;
align-items: center;
transition: height 0.4s;
}
.box > li.open{
display: flex;
}
.red{
color:red;
}
.blue{
color:blue
}
const { ref, reactive, readonly, computed } = Vue;
const App = {
setup () {
// 用 Vue.ref() 作綁定, 綁定後會有一個屬性為 value
// 修改其 value 後,畫面值會變動
const isOpen = ref(true)
const text = ref('Hello Vue!')
const number = ref(0)
const copyNumber = readonly(number)
const countryCodes = ref([
{ name: 'Taiwan', code: '886', show: true, class: 'red' },
{ name: 'Japan', code: '81', show: true, class: 'red' },
{ name: 'United States', code: '1', show: false, class: 'blue' },
{ name: 'United Kingdom', code: '44', show: true, class: 'blue' },
{ name: 'Singapore', code: '65', show: true, class: 'blue' }
])
// reactive 僅接受 [],{},可以進行深層檢查,不需要用 .value 就可以取得值
const message = reactive({ name: 'Steve Jobs', show: true })
const indexInObject = reactive({ index: 0 })
// 若你有方法要給 template 的模板作操作,那一定要在 setup 中 return
const add = () => {
number.value += 1
indexInObject.index += 2
}
const minus = () => {
number.value -= 1
indexInObject.index -= 2
}
const addToReadOnly = () => {
copyNumber.value += 1
}
const changeMessageStatus = () => {
message.show ? message.show = false : message.show = true
}
const displayCountryCode = () => {
isOpen.value = !isOpen.value
}
// 經由 computed 計算後,若要取值都得加上 .value
const multipleNumber = computed(() => {
return number.value * 5
})
setTimeout(() => {
text.value = 'Hello World!'
}, 1000)
return { text, message, number, add, minus, indexInObject, addToReadOnly, countryCodes, changeMessageStatus, isOpen, displayCountryCode, multipleNumber }
}
}
Vue.createApp(App).mount("#app");
Also see: Tab Triggers