This article mainly introduces the use of vue computed properties and method examples of vue instances. The editor thinks it is quite good. Now I will share it with you and give it a reference. Let’s follow the editor and take a look.
This article introduces the use of vue calculated properties and examples of methods of vue instances. I would like to share them with you. The details are as follows:
Computed properties
Expressions are very convenient in templates, but they are really only used for simple operations. Templates are used to describe the structure of views. Putting too much logic into a template can make it overweight and difficult to maintain. That's why Vue.js limits binding expressions to one expression. If the logic of more than one expression is required, computed properties should be used.
vue computed properties
When we want to return the value of a property based on the execution result of one end of the business code, we can use the computed property computed,
Computed property is a function with results. It has get method and set method. The get method must have a return value and must have a return value.
<script src="lib/vue.js"></script>
<body>
<p id="box">
a = >{{a}}
b = > {{b}}
</p>
</body>
<script>
var vm = new Vue({
el:'#box',
data:{
a:1
},
computed:{
b:function () {
//业务代码
return this.a+1;
}
}
});
/**这样直接改属性的值不行的，需要调用计算属性的set方法**/
document.onclick = function(){
vm.b = 3;
};
</script>The set/get method of calculated property:
<script src="lib/vue.js"></script>
<body>
<p id="box">
a = >{{a}}
b = > {{b}}
</p>
</body>
<script>
var vm = new Vue({
el:'#box',
data:{
a:1
},
computed:{
b:{
get:function () {
return this.a+1;
},
set:function(val){
this.a = val;
}
}
}
});
/**这样直接改属性的值不行的，需要调用计算属性的set方法**/
document.onclick = function(){
vm.b = 3;
//默认调用计算属性的set方法
};
</script>Simple method of vue instance
vm is the name of the created vue instance object
vm.$el -> is the element
vm. $data -> is data
vm.$mount -> Mount the vue object on the node object
For example:
var vm2 = new Vue({
data:{},
methods:{}
}).$mount('#box');is equivalent to:
var vm2 = new Vue({
el:'#box',
data:{},
methods:{}
});vm.$options -> Get custom properties, custom methods
Vue instances can customize properties and methods. If you need to call them, you need to call $options. For example:
var vm2 = new Vue({
aa:'1',//自定义属性
show:function () {
alert(1);
},
el:'#box',
data:{},
methods:{}
});
vm2.$options.show();
console.log(vm2.$options.aa);vm.$destroy -> Destroy the object
vm.$log(); -> Check the current status of the data
The above is what I compiled for everyone, I hope It will be helpful to everyone in the future.
Related articles:
How to use the swiper component to implement image switching display in WeChat Mini Program
How to implement circular advertising in javascript Article
About the debugging tool vue-devtools (detailed tutorial) in Vue
The above is the detailed content of How to use calculated properties in vue. For more information, please follow other related articles on the PHP Chinese website!
JavaScript's Core: Is It Built on C or C ?May 05, 2025 am 12:07 AMJavaScriptisnotbuiltonCorC ;it'saninterpretedlanguagethatrunsonenginesoftenwritteninC .1)JavaScriptwasdesignedasalightweight,interpretedlanguageforwebbrowsers.2)EnginesevolvedfromsimpleinterpreterstoJITcompilers,typicallyinC ,improvingperformance.
JavaScript Applications: From Front-End to Back-EndMay 04, 2025 am 12:12 AMJavaScript can be used for front-end and back-end development. The front-end enhances the user experience through DOM operations, and the back-end handles server tasks through Node.js. 1. Front-end example: Change the content of the web page text. 2. Backend example: Create a Node.js server.
Python vs. JavaScript: Which Language Should You Learn?May 03, 2025 am 12:10 AMChoosing Python or JavaScript should be based on career development, learning curve and ecosystem: 1) Career development: Python is suitable for data science and back-end development, while JavaScript is suitable for front-end and full-stack development. 2) Learning curve: Python syntax is concise and suitable for beginners; JavaScript syntax is flexible. 3) Ecosystem: Python has rich scientific computing libraries, and JavaScript has a powerful front-end framework.
JavaScript Frameworks: Powering Modern Web DevelopmentMay 02, 2025 am 12:04 AMThe power of the JavaScript framework lies in simplifying development, improving user experience and application performance. When choosing a framework, consider: 1. Project size and complexity, 2. Team experience, 3. Ecosystem and community support.
The Relationship Between JavaScript, C , and BrowsersMay 01, 2025 am 12:06 AMIntroduction I know you may find it strange, what exactly does JavaScript, C and browser have to do? They seem to be unrelated, but in fact, they play a very important role in modern web development. Today we will discuss the close connection between these three. Through this article, you will learn how JavaScript runs in the browser, the role of C in the browser engine, and how they work together to drive rendering and interaction of web pages. We all know the relationship between JavaScript and browser. JavaScript is the core language of front-end development. It runs directly in the browser, making web pages vivid and interesting. Have you ever wondered why JavaScr
Node.js Streams with TypeScriptApr 30, 2025 am 08:22 AMNode.js excels at efficient I/O, largely thanks to streams. Streams process data incrementally, avoiding memory overload—ideal for large files, network tasks, and real-time applications. Combining streams with TypeScript's type safety creates a powe
Python vs. JavaScript: Performance and Efficiency ConsiderationsApr 30, 2025 am 12:08 AMThe differences in performance and efficiency between Python and JavaScript are mainly reflected in: 1) As an interpreted language, Python runs slowly but has high development efficiency and is suitable for rapid prototype development; 2) JavaScript is limited to single thread in the browser, but multi-threading and asynchronous I/O can be used to improve performance in Node.js, and both have advantages in actual projects.
The Origins of JavaScript: Exploring Its Implementation LanguageApr 29, 2025 am 12:51 AMJavaScript originated in 1995 and was created by Brandon Ike, and realized the language into C. 1.C language provides high performance and system-level programming capabilities for JavaScript. 2. JavaScript's memory management and performance optimization rely on C language. 3. The cross-platform feature of C language helps JavaScript run efficiently on different operating systems.
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
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Atom editor mac version download
The most popular open source editor
Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.
EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function
mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),
PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool
