Understanding Javascript object literals (graphic tutorial)
This article mainly introduces the understanding of Javascript object literals. It is easy to understand and friends in need can refer to it.
Object literal output methods and definition benefits
1. There are two output methods for object literals: traditional ‘. ', and array mode, But when outputting in array mode, the square brackets must be enclosed in quotation marks, such as
var box = { name:'abc'; age:28 }; alert(box['name']);
Define methods for objects,
A: If you use the traditional way of defining an object, you need to define the method first, and then assign the method name to an attribute of the object. If you want Calling this method without parentheses will return the method code; if you want to call this method with parentheses after the object attribute, you will get the return value of the method
function objrun(){ return '123'; } var box = new Object(); box.name='abc'; box.age = 28; box.run = objrun; alert(box.run()); //结果为123 // alert(box.run); //结果为function objrun(){ return '123'; } //如果box.run = objrun(); //alert(box.run); //结果为123,如果带上圆括号,就报错啦
B:Use Literal definition , just need to write function directly on this attribute of the object. There is no function name on this function. It is an anonymous function . So how to call this method? Use To call a method using this property name of an object, just do the same as above
For example:
var box = { name:'abc', age:28, run:function(){ return '123'; } } alert(box.run());
2. The definition of object literals can easily handle the situation where a large number of function parameters need to be output in one-to-one correspondence. His solution is to pass an object into the function, and this object is defined in a literal way. The corresponding properties and values can make their relationship clear at a glance , because the function is just a piece of code and must be called. Execute
For example:
function AA(obj){ alert(obj.name); alert(obj.age); } var obj = { name: 'abc', age: 28 } AA(obj);
js object literal demo
/** * @author zhanghua */ var literal = { add: function(){ alert("add"); }, del: function(){ alert("delete"); }, update: function(){ alert("update"); }, name: "zhangsan", callLiteral: function(){ // 对于当前字面量对象的调用,要加this关键字 this.add(); } };
html file:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>Literal--字面量</title> <script type="text/javascript" src="jslib/literal.js"></script> </head> <body> <input type="button" value="add" onclick="javascript:literal.add()"/> <input type="button" value="delete" onclick="javascript:literal.del()"/> <input type="button" value="update" onclick="literal.update()"/> <input type="button" value="name" onclick="javascript:alert(literal.name)"/> <input type="button" value="name" onclick='javascript:alert(literal["name"])'"/> <input type="button" value="caller" onclick='javascript:literal.callLiteral()'"/> </body> </html>
The above is what I compiled Everyone, I hope it will be helpful to everyone in the future.
Related articles:
Related js Real-time monitoring of changes in input values (graphic tutorial)
##js Summary of common methods of string() (graphic tutorial)
What are the methods for php to read local json files
The above is the detailed content of Understanding Javascript object literals (graphic tutorial). For more information, please follow other related articles on the PHP Chinese website!

Python and JavaScript each have their own advantages, and the choice depends on project needs and personal preferences. 1. Python is easy to learn, with concise syntax, suitable for data science and back-end development, but has a slow execution speed. 2. JavaScript is everywhere in front-end development and has strong asynchronous programming capabilities. Node.js makes it suitable for full-stack development, but the syntax may be complex and error-prone.

JavaScriptisnotbuiltonCorC ;it'saninterpretedlanguagethatrunsonenginesoftenwritteninC .1)JavaScriptwasdesignedasalightweight,interpretedlanguageforwebbrowsers.2)EnginesevolvedfromsimpleinterpreterstoJITcompilers,typicallyinC ,improvingperformance.

JavaScript 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.

Choosing 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.

The 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.

Introduction 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 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

The 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.


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

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

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.

MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

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

DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software
