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v-text
v-text is mainly used to update textContent, which can be equivalent to the text attribute of JS.
<span v-text="text"></span>
// 等同于下方语句：
<span>{{text}}</span>v-html
The double brace method will interpret the data as plain text, not HTML. In order to output real HTML, you can use the v-html command. It is equivalent to JS's innerHtml property.
Note: Content is inserted as normal HTML - will not be compiled as a Vue template.
<div v-html="html"></div>
v-show
Equivalent to css's dispaly attribute switching between "none" and "block" settings.
<div v-show="isShow">hello world</div>
v-if
v-if can implement conditional rendering. Vue will render elements based on the true and false conditions of the expression value. .
<div v-show="isShow">hello world</div>
The above code, if isShow is false, the div is rendered, otherwise it is not rendered.
Note:
v-if needs to be distinguished from v-show. The elements of v-show will always be rendered and saved in the dom. It just simply switches the dispaly attribute of css.
v-if has higher switching overhead.
v-show has higher initial rendering overhead.
So, if you want to switch very frequently, it is better to use v-show; if the conditions are unlikely to change during runtime, it is better to use v-if.
v-else
v-else is used with v-if, it must follow v-if or v-else -if after, otherwise it has no effect.
Similar to JS’s if .. else.
<div v-if="isSow">值为true的时候显示的内容</div> <div v-else>值为false的时候显示的内容</div>
v-else-if
v-else-if acts as the else-if block of v-if and can be used in a chain repeatedly. Similar to JS's if .. else if .. else
<div v-if="type==='A'"> A </div> <div v-if="type==='B'"> B </div> <div v-if="type==='C'"> C </div> <div v-else> Not A,B,C </div>
v-for
Use the v-for instruction to render by traversing the array .
<ul>
<li v-for="item in items">{{item.name}}</li>
</ul>
<script>
new Vue({
el: '#app',
data: {
items: [
{ name: 'Runoob' },
{ name: 'Google' },
{ name: 'Taobao' }
]
}
})
</script>
// 补充：
// 也可以自行指定参数，最多可以接受3个参数
<div v-for="(item, index) in items"></div>
<div v-for="(val, key) in object"></div>
<div v-for="(val, name, index) in object"></div>
// 迭代对象
<ul>
<li v-for="value in object">
{{ index }}. {{ key }} : {{ value }}
</li>
// 迭代整数
<ul>
<li v-for="n in 10">
{{ n }}
</li>
</ul>v-on
Bind event listener. The event type is specified by parameters. The expression can be the name of a method or an inline statement, and can be omitted if there are no modifiers.
v-on can also be abbreviated as "@", such as:
v-on="show" can be abbreviated as: @show
<!-- 方法处理器 -->
<button v-on:click="doThis"></button>
<!-- 动态事件 (2.6.0+) -->
<button v-on:[event]="doThis"></button>
<!-- 内联语句 -->
<button v-on:click="doThat('hello', $event)"></button>
<!-- 缩写 -->
<button @click="doThis"></button>
<!-- 动态事件缩写 (2.6.0+) -->
<button @[event]="doThis"></button>
<!-- 停止冒泡 -->
<button @click.stop="doThis"></button>
<!-- 阻止默认行为 -->
<button @click.prevent="doThis"></button>
<!-- 阻止默认行为，没有表达式 -->
<form @submit.prevent></form>
<!-- 串联修饰符 -->
<button @click.stop.prevent="doThis"></button>
<!-- 键修饰符，键别名 -->
<input @keyup.enter="onEnter">
<!-- 键修饰符，键代码 -->
<input @keyup.13="onEnter">
<!-- 点击回调只会触发一次 -->
<button v-on:click.once="doThis"></button>
<!-- 对象语法 (2.4.0+) -->
<button v-on="{ mousedown: doThis, mouseup: doThat }"></button>You can also use modifiers, as follows :
.stop - Call event.stopPropagation().
.prevent - Calls event.preventDefault().
.capture - Use capture mode when adding event listeners.
.self - The callback is only triggered when the event is triggered from the element itself to which the listener is bound.
.{keyCode | keyAlias} - The callback is only fired when the event is triggered from a specific key.
.native - Listen to native events on the root element of the component.
.once - The callback is triggered only once.
.left - only fires when the left mouse button is clicked.
.right - only triggered when the right mouse button is clicked.
.middle - only triggered when the middle mouse button is clicked.
.passive - add a listener in { passive: true } mode
v-bind
Dynamically bind one or more attributes, or a component prop to an expression. Often used to dynamically bind classes and styles. And href etc.
can be abbreviated as: " : ", such as:
v-bind:class=" isActive : 'active' :' ' ", can be abbreviated as: :class=" isActive : ' active' :' ' "
<div v-bind:class=" isActive : 'active' :' ' "></div>
<script>
var app = new Vue({
el: '#app',
data: {
isActive : true,
}
})
</script>
//渲染结果为： <div class="active"></div>Bind multiple classes, the details are as follows:
<div v-bind:class="[ isActive : 'active' :' ' , isError: 'error' :' ' ]">
</div>
<script>
var app = new Vue({
el: '#app',
data: {
isActive : true,
isError: true,
}
})
</script>
//渲染结果为： <div class="active error"></div>Other examples, see the code below for details:
<!-- 绑定一个属性 -->
<img v-bind:src="imageSrc">
<!-- 动态特性名 (2.6.0+) -->
<button v-bind:[key]="value"></button>
<!-- 缩写 -->
<img :src="imageSrc">
<!-- 动态特性名缩写 (2.6.0+) -->
<button :[key]="value"></button>
<!-- 内联字符串拼接 -->
<img :src="'/path/to/images/' + fileName">
<!-- class 绑定 -->
<div :class="{ red: isRed }"></div>
<div :class="[classA, classB]"></div>
<div :class="[classA, { classB: isB, classC: isC }]">
<!-- style 绑定 -->
<div :style="{ fontSize: size + 'px' }"></div>
<div :style="[styleObjectA, styleObjectB]"></div>
<!-- 绑定一个有属性的对象 -->
<div v-bind="{ id: someProp, 'other-attr': otherProp }"></div>
<!-- 通过 prop 修饰符绑定 DOM 属性 -->
<div v-bind:text-content.prop="text"></div>
<!-- prop 绑定。“prop”必须在 my-component 中声明。-->
<my-component :prop="someThing"></my-component>
<!-- 通过 $props 将父组件的 props 一起传给子组件 -->
<child-component v-bind="$props"></child-component>
<!-- XLink -->
<svg><a :xlink:special="foo"></a></svg>v-model
#Create two-way binding on a form control or component.
v-model will ignore the initial values of the value, checked, and selected attributes of all form elements. Because it selects Vue instance data as the specific value.
<div id="app">
<input v-model="somebody">
<p>hello {{somebody}}</p>
</div>
<script>
var app = new Vue({
el: '#app',
data: {
somebody:'小明'
}
})
</script>In this example, enter another name directly into the browser input, and the content of the p below will change directly accordingly. This is two-way data binding.
Available modifiers:
.lazy - By default, v-model synchronizes the value and data of the input box. You can use this modifier to switch to resynchronization in the change event.
.number - Automatically convert the user's input value into a numerical type
.trim - Automatically filter the leading and trailing spaces entered by the user
How to use modifiers: For example:
<input v-model.trim="somebody">
v-pre
v-pre is mainly used to skip the compilation process of this element and its sub-elements. Can be used to display the original Mustache tag. Skip a large number of nodes without instructions to speed up compilation.
<div id="app">
<span v-pre>{{message}}</span> //这条语句不进行编译
<span>{{message}}</span>
</div>This directive is used to remain on the element until the end of the associated instance for compilation.
<div id="app" v-cloak>
<div>
{{message}}
</div>
</div>
<script type="text/javascript">
new Vue({
el:'#app',
data:{
message:'hello world'
}
})
</script>Explanation:
will flash when the page is loaded. It will first display:
<div>
{{message}}
</div>and then compile to:
<div> hello world! </div>
The v-cloak command can To solve the problem of interpolation flickering above, as follows: In fact, what is used is to hide the content through the style attribute when the interpolation is not loaded.
<style>
[v-cloak] {
display: none;
}
</style>
<div id="app">
<!-- 使用 v-cloak 能够解决 插值表达式闪烁的问题 -->
<p v-cloak>++++++++ {{ msg }} ----------</p>
</div>
<script>
var vm = new Vue({
el: '#app',
data: {
msg: 'hello',
}
})
</script>v-once
v-once关联的实例，只会渲染一次。之后的重新渲染，实例极其所有的子节点将被视为静态内容跳过，这可以用于优化更新性能。
<span v-once>This will never change:{{msg}}</span> //单个元素
<div v-once>//有子元素
<h1>comment</h1>
<p>{{msg}}</p>
</div>
<my-component v-once:comment="msg"></my-component> //组件
<ul>
<li v-for="i in list">{{i}}</li>
</ul>上面的例子中，msg,list即使产生改变，也不会重新渲染。
v-slot
提供具名插槽或需要接收 prop 的插槽。
可简写为：#
slot 和 scope-slot 是在 vue@2.6.x 之前的语法，而从 vue@2.6.0 开始，官方推荐我们使用 v-slot 来替代前两者。
使用具名插槽来自定义模板内容（vue@2.6.x已经废弃）
<div class="container">
<header>
<slot name="header"></slot>
</header>
<main>
<slot></slot>
</main>
<footer>
<slot name="footer"></slot>
</footer>
</div>在向具名插槽提供内容的时候，我们可以在一个父组件的 元素上使用 slot 特性：
<base-layout>
<template slot="header">
<h1>Here might be a page title</h1>
</template>
<p>A paragraph for the main content.</p>
<p>And another one.</p>
<template slot="footer">
<p>Here's some contact info</p>
</template>
</base-layout>接下来，使用 v-slot 指令改写上面的栗子：
<base-layout>
<template v-slot:header>
<h1>Here might be a page title</h1>
</template>
<p>A paragraph for the main content.</p>
<p>And another one.</p>
<template v-slot:footer>
<p>Here's some contact info</p>
</template>
</base-layout>使用 # 简写代替 v-slot
<base-layout>
<template #header>
<h1>Here might be a page title</h1>
</template>
<p>A paragraph for the main content.</p>
<p>And another one.</p>
<template #footer>
<p>Here's some contact info</p>
</template>
</base-layout>相关推荐：
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