响应式
声明状态
更新状态
模板语法
样式
DOM循环
点击事件
<script setup>
import { ref } from "vue";
const count = ref(0);
function incrementCount() {
count.value++;
}
</script>
<template>
<p>计数器: {{ count }}</p>
<button @click="incrementCount">+1</button>
</template>
Ember Octane
<p>计数器: {{this.count}}</p>
<button {{on "click" this.incrementCount}}>+1</button>DOM引用
条件渲染
<script setup>
import { ref, computed } from "vue";
const TRAFFIC_LIGHTS = ["红灯", "黄灯", "绿灯"];
const lightIndex = ref(0);
const light = computed(() => TRAFFIC_LIGHTS[lightIndex.value]);
function nextLight() {
lightIndex.value = (lightIndex.value + 1) % TRAFFIC_LIGHTS.length;
}
</script>
<template>
<button @click="nextLight">下一个灯</button>
<p>现在亮着的是: {{ light }}</p>
<p>
你应该
<span v-if="light === '红灯'">停下</span>
<span v-else-if="light === '黄灯'">慢行</span>
<span v-else-if="light === '绿灯'">赶紧走</span>
</p>
</template>
Ember Octane
<button {{on "click" this.nextLight}}>下一个灯</button>
<p>现在亮着的是: {{this.light}}</p>
<p>
你应该
{{#if (eq this.light "红灯")}}
停下
{{else if (eq this.light "黄灯")}}
慢行
{{else if (eq this.light "绿灯")}}
赶紧走
{{/if}}
</p>生命周期
组件加载时
组件卸载时
<script setup>
import { ref, onUnmounted } from "vue";
const time = ref(new Date().toLocaleTimeString());
const timer = setInterval(() => {
time.value = new Date().toLocaleTimeString();
}, 1000);
onUnmounted(() => {
clearInterval(timer);
});
</script>
<template>
<p>当前时间: {{ time }}</p>
</template>
Ember Octane
<p>当前时间: {{this.time}}</p>组件组合
组件Props传参
<script setup>
import UserProfile from "./UserProfile.vue";
</script>
<template>
<UserProfile
name="张三"
:age="20"
:favourite-colors="['green', 'blue', 'red']"
is-available
/>
</template>
Ember Octane
<UserProfile
@name="张三"
@age={{20}}
@favouriteColors={{array "green" "blue" "red"}}
@isAvailable={{true}}
/>向父组件emit事件
<script setup>
import { ref } from "vue";
import AnswerButton from "./AnswerButton.vue";
let isHappy = ref(true);
function onAnswerNo() {
isHappy.value = false;
}
function onAnswerYes() {
isHappy.value = true;
}
</script>
<template>
<p>你快乐吗?</p>
<AnswerButton @yes="onAnswerYes" @no="onAnswerNo" />
<p style="font-size: 50px">
{{ isHappy ? "😀" : "😥" }}
</p>
</template>
Ember Octane
<p>你快乐吗?</p>
<AnswerButton @onYes={{this.handleYes}} @onNo={{this.handleNo}} />
<p style="font-size: 50px;">{{if this.isHappy "😀" "😥"}}</p>slot插槽
slot插槽内容
上下文
<script setup>
import { ref, provide } from "vue";
import UserProfile from "./UserProfile.vue";
const user = ref({
id: 1,
username: "abcdefg",
email: "[email protected]",
});
function updateUsername(username) {
user.value.username = username;
}
provide("user", { user, updateUsername });
</script>
<template>
<h1>欢迎回来, {{ user.username }}</h1>
<UserProfile />
</template>
Ember Octane
<UserProfile />表单输入
输入框
复选框
<script setup>
import { ref } from "vue";
const isAvailable = ref(true);
</script>
<template>
<input id="is-available" v-model="isAvailable" type="checkbox" />
<label for="is-available">这是一个checkbox</label>
</template>
Ember Octane
<input
id="is-available"
type="checkbox"
checked={{this.isAvailable}}
{{on "change" this.handleChange}}
/>
<label for="is-available">这是一个checkbox</label>单选框
<script setup>
import { ref } from "vue";
const picked = ref("red");
</script>
<template>
<div>你选择了: {{ picked }}</div>
<input id="blue-pill" v-model="picked" type="radio" value="blue" />
<label for="blue-pill">蓝色</label>
<input id="red-pill" v-model="picked" type="radio" value="red" />
<label for="red-pill">红色</label>
</template>
Ember Octane
<div>你选择了: {{this.picked}}</div>
<input
id="blue-pill"
type="radio"
value="blue"
checked={{eq this.picked "blue"}}
{{on "change" this.handleChange}}
/>
<label htmlFor="blue-pill">蓝色</label>
<input
id="red-pill"
type="radio"
value="red"
checked={{eq this.picked "red"}}
{{on "change" this.handleChange}}
/>
<label htmlFor="red-pill">红色</label>选择器
<script setup>
import { ref } from "vue";
const selectedColorId = ref(2);
const colors = [
{ id: 1, text: "红" },
{ id: 2, text: "蓝" },
{ id: 3, text: "绿" },
{ id: 4, text: "灰", isDisabled: true },
];
</script>
<template>
<select v-model="selectedColorId">
<option
v-for="color in colors"
:key="color.id"
:value="color.id"
:disabled="color.isDisabled"
>
{{ color.text }}
</option>
</select>
</template>
Ember Octane
<select {{on "change" this.select}}>
{{#each this.colors as |color|}}
<option
value={{color.id}}
disabled={{color.isDisabled}}
selected={{eq color.id this.selectedColorId}}
>
{{color.text}}
</option>
{{/each}}
</select>Web应用特性
渲染应用
<!doctype html>
<html>
<body>
<div id="app"></div>
<script type="module" src="./main.js"></script>
</body>
</html>
Ember Octane
缺少代码片段 帮助我们改进 Component Party 
fetch获取数据
<script setup>
import useFetchUsers from "./useFetchUsers";
const { isLoading, error, data: users } = useFetchUsers();
</script>
<template>
<p v-if="isLoading">正在获取用户信息……</p>
<p v-else-if="error">获取用户信息出错</p>
<ul v-else-if="users">
<li v-for="user in users" :key="user.login.uuid">
<img :src="user.picture.thumbnail" alt="user" />
<p>
{{ user.name.first }}
{{ user.name.last }}
</p>
</li>
</ul>
</template>
Ember Octane
{{#let (this.fetchUsers) as |request|}}
{{#if request.isLoading}}
<p>正在获取用户信息……</p>
{{else if request.error}}
<p>获取用户信息出错</p>
{{else}}
<ul>
{{#each request.users as |user|}}
<li>
<img src={{user.picture.thumbnail}} alt="user" />
<p>{{user.name.first}} {{user.name.last}}</p>
</li>
{{/each}}
</ul>
{{/if}}
{{/let}}