How does v-bind dynamically bind class attributes? This article will give you a detailed understanding of the various syntaxes of the v-bind instruction to dynamically bind class attributes. I hope it will be helpful to you!
#v-bind can dynamically set the class attribute to implement dynamic styles. Writing method:
<!--完整写法--> <标签名 v-bind:class="vue实例中的数据属性名"/> <!--简化写法--> <标签名 :class="vue实例中的数据属性名"/>
1. v-bind dynamically binds the class attribute (object syntax)
After dynamically binding the class attribute, the class The value is a variable that can be placed in data to dynamically bind the style to dynamically switch classes. (Learning video sharing: vue video tutorial)
1. Directly bind one or more classes through {}
v-blid:class
can pass in an object, which includes a set of key-value pairs
:class= "{key1:value1,key2:value2...}"
The class name is the corresponding style, that is, the key ); value corresponds to adding and removing the class, the values are true
and false
if value is
true
, then the key style will workIf the value value is
false
, then the key style will not work
<!-- 样式 --> <style> .color { color: red; } .background { background-color: pink; } </style>
<div id="app"> <h2 id="message">{{message}}</h2> <!-- 第一种:直接用style中的样式,固定写死; --> <h2 id="message">{{message}}</h2> <!-- 第二种:用指令v-bind,class的属性值color为变量; --> <!-- vue解析,变量对应data中color属性值,则用了color的样式; --> <h2 id="message">{{message}}</h2> <!-- 第三种:用指令v-bind;后面接对象{key1:value1,key2:value2} --> <!-- isColor为false则color样式不起作用。 --> <!-- isBackground为true则background样式起作用。 --> </div> <script> const app = new Vue({ el:"#app", data:{ message:"你好啊", color:"color", isColor:false, isBackground:true } }) </script>
v-bind:class
directive can also coexist with the ordinary class attribute.
<div class="static" v-bind:class="{ active: isActive, 'text-danger': hasError }" ></div>
data: { isActive: true, hasError: true }
When isActive
or hasError
changes, the class list will be updated accordingly. For example, if hasError
has the value false
, the class list will become "static active
".
data: { isActive: true, hasError: false }
2. The bound data object does not need to be defined inline in the template, but can be bound to a class object classObject
<!-- 样式 --> <style> .color { color: red; } .background { background-color: pink; } </style>
<div id="app"> <h2 id="message">{{message}}</h2> <!-- 如下:绑定到一个类对象classObject,对象中设置多个key:value对 --> <!-- color为true则color样式起作用。 --> <!-- background为false则background样式不起作用。 --> </div> <script> const app = new Vue({ el:"#app", data:{ message:"你好啊", classObject: { color: true, background: false } } }) </script>
3. You can also bind a calculated property of the returned object
<div id="app"> <h2 id="message">{{message}}</h2> <!-- 如下:绑定到一个类对象classObject,对象中设置多个key:value对 --> <!-- color为true则color样式起作用。 --> <!-- background为false则background样式不起作用。 --> </div> <script> const app = new Vue({ el:"#app", data:{ message:"你好啊", isColor: true, isBackground: true }, computed: { classObject: function () { return { color: this.isColor, background: this.isBackground } } } }) </script>
4. If the objects in the class are more complex, put them directly in a method, and then call this function to achieve dynamic switching
<!DOCTYPE html> <html> <head> <script type="text/javascript" ></script> <style> .active{ background-color: pink; } .line{ color: red; } </style> </head> <body> <div id="app"> <h2 id="方法methods-message">方法methods:{{message}}</h2> <h2 id="计算属性computed-message">计算属性computed:{{message}}</h2> <button v-on:click="btnClick">按钮</button> </div> <script> const app = new Vue({ el: '#app', data: { message: '你好啊', active:'active', isAcitve:true, isLine:true }, methods:{ btnClick: function () { this.isAcitve = !this.isAcitve },getClasses:function () { return {active:this.isAcitve,line:this.isLine} } }, computed: { classes: function () { return {active:this.isAcitve,line:this.isLine} } } }) </script> </body> </html>
##2. v-bind dynamically binds class attributes (array syntax)
We can pass an array to:class to apply a class List;
:class="[base1,base2]"v-bind Dynamically binding class array syntax is to directly pass in an array, but the array is full of class names. The class name will be added to this tag in the page. The style is changed by adding or subtracting elements in the array.
Note: The class names here need to be wrapped withNote: It is the same as the object syntax and can exist at the same time as an ordinary class without conflict' '
. If not wrapped, Vue will treat it as an attribute in data and go to data Searching inside, obviously there is no such attribute in the data, so the error will come. This is common in Vue. Without quotation marks, it is treated as an attribute in data
<h2 id="message">{{message}}</h2>
<h2 id="message">{{message}}</h2> <h2 id="message">{{message}}</h2> <h2 id="message">{{message}}</h2><script> const app = new Vue({ el: '#app', data: { message: '你好啊', active:'active', line:'bbbbbbbbbb' }, methods:{ getClasses: function () { return [this.active,this.line] } }, computed: { classes: function () { return [this.active,this.line] } } }) </script>方法methods:{{message}}
计算属性computed:{{message}}
<div v-bind:class="[isActive ? activeClass : '', errorClass]"></div>Writing like this will always add errorClass, but only add activeClass when isActive is true. However, it is a bit cumbersome to write like this when there are multiple conditional classes. Therefore, object syntax can also be used in array syntax:
<div v-bind:class="[{ active: isActive }, errorClass]"></div>Example:
<!DOCTYPE html> <html> <head> <script type="text/javascript" ></script> <style> .aaa{ padding: 10px; } .active{ background-color: pink; } .line{ color: red; } </style> </head> <body> <div id="app"> <div :class="['aaa','active']">{{message}}</div> <div :class="['aaa', nba, isActive? 'active': '']">{{message}}</div> <div :class="['aaa', nba, {'actvie': isActive}]">{{message}}</div> </div> <script> const app = new Vue({ el: '#app', data() { return { message: "Hello World", nba: 'line', isActive: false } } }) </script> </body> </html>
web front-end development ,Basic Programming Video)
The above is the detailed content of Detailed explanation of how v-bind dynamically binds class attributes. For more information, please follow other related articles on the PHP Chinese website!

vue中props可以传递函数;vue中可以将字符串、数组、数字和对象作为props传递,props主要用于组件的传值,目的为了接收外面传过来的数据,语法为“export default {methods: {myFunction() {// ...}}};”。

本篇文章带大家聊聊vue指令中的修饰符,对比一下vue中的指令修饰符和dom事件中的event对象,介绍一下常用的事件修饰符,希望对大家有所帮助!

如何覆盖组件库样式?下面本篇文章给大家介绍一下React和Vue项目中优雅地覆盖组件库样式的方法,希望对大家有所帮助!

react与vue的虚拟dom没有区别;react和vue的虚拟dom都是用js对象来模拟真实DOM,用虚拟DOM的diff来最小化更新真实DOM,可以减小不必要的性能损耗,按颗粒度分为不同的类型比较同层级dom节点,进行增、删、移的操作。


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

Dreamweaver Mac version
Visual web development tools

Notepad++7.3.1
Easy-to-use and free code editor

VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft
