This time I will bring you tips on how to use DOM event binding in js. What are the precautions when using DOM event binding in js? Here are practical cases, let’s take a look.
js event binding
JavaScript has three event models:
Inline model
Script model
DOM2 model
##1. Inline model
//基本废除不用 <input> <input>
2. Script model
//基本不用 var input = document.getElementsByTagName('input')[0]; //得到 input 对象 input.onclick = function () { //匿名函数执行 alert('Lee'); }; 事件处理函数 影响的元素 何时发生 onabort 图像 当图像加载被中断时 onblur 窗口、框架、所有表单对象 当焦点从对象上移开时 onchange 输入框,选择框和文本区域 当改变一个元素的值且失去焦点时 onclick 链接、按钮、表单对象、图像映射区域 当用户单击对象时 ondblclick 链接、按钮、表单对象 当用户双击对象时 ondragdrop 窗口 当用户将一个对象拖放到浏览器窗口时 onError 脚本 当脚本中发生语法错误时 onfocus 窗口、框架、所有表单对象 当单击鼠标或者将鼠标移动聚焦到窗口或框架时 onkeydown 文档、图像、链接、表单 当按键被按下时 onkeypress 文档、图像、链接、表单 当按键被按下然后松开时 onkeyup 文档、图像、链接、表单 当按键被松开时 onload 主题、框架集、图像 文档或图像加载后 onunload 主体、框架集 文档或框架集卸载后 onmouseout 链接 当图标移除链接时 onmouseover 链接 当鼠标移到链接时 onmove 窗口 当浏览器窗口移动时 onreset 表单复位按钮 单击表单的 reset 按钮 onresize 窗口 当选择一个表单对象时 onselect 表单元素 当选择一个表单对象时 onsubmit 表单 当发送表格到服务器时
3. Inline model
"DOM2-level events" defines two methods for adding events And operations to remove event handlers:addEventListener() and removeEventListener(). These two methods are included in all DOM nodes, and they both accept 3 parameters; event name, function, bubbling or captured Boolean value (true means capturing, false means bubbling)
window.addEventListener('load', function () { alert('Lee'); }, false); window.removeEventListener('load', function () { alert('Mr.Lee'); }, false)PS: IE implements two methods similar to those in DOM: attachEvent() and detachEvent(). Both methods accept
the same parameters: event name and function.
1. IE 不支持捕获,只支持冒泡; 2. IE 添加事件不能屏蔽重复的函数; 3. IE 中的 this 指向的是 window 而不是 DOM 对象。 4. 在传统事件上,IE 是无法接受到 event 对象的,但使用了 attchEvent()却可以,但有些区别。 "javascript window.attachEvent('load', function () { alert('Lee'); }, false); window.detachEvent('load', function () { alert('Mr.Lee'); }, false) "PS: The event binding functions attachEvent() and detachEvent() in IE may not be used in practice There are several reasons for using: 1. IE9 will fully support the event binding function in W3C; 2. IE’s event binding function cannot pass this; 3. IE's event binding function does not support capture; 4. After the same function is registered and bound, it is not blocked; 5. There is a memory leak problem
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website! Recommended reading:
Angular CLI generates Angular 5 project usage detailed explanation
The above is the detailed content of Tips on using DOM event binding in js. For more information, please follow other related articles on the PHP Chinese website!

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.

JavaScript 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.

JavaScript runs in browsers and Node.js environments and relies on the JavaScript engine to parse and execute code. 1) Generate abstract syntax tree (AST) in the parsing stage; 2) convert AST into bytecode or machine code in the compilation stage; 3) execute the compiled code in the execution stage.

The future trends of Python and JavaScript include: 1. Python will consolidate its position in the fields of scientific computing and AI, 2. JavaScript will promote the development of web technology, 3. Cross-platform development will become a hot topic, and 4. Performance optimization will be the focus. Both will continue to expand application scenarios in their respective fields and make more breakthroughs in performance.

Both Python and JavaScript's choices in development environments are important. 1) Python's development environment includes PyCharm, JupyterNotebook and Anaconda, which are suitable for data science and rapid prototyping. 2) The development environment of JavaScript includes Node.js, VSCode and Webpack, which are suitable for front-end and back-end development. Choosing the right tools according to project needs can improve development efficiency and project success rate.

Yes, the engine core of JavaScript is written in C. 1) The C language provides efficient performance and underlying control, which is suitable for the development of JavaScript engine. 2) Taking the V8 engine as an example, its core is written in C, combining the efficiency and object-oriented characteristics of C. 3) The working principle of the JavaScript engine includes parsing, compiling and execution, and the C language plays a key role in these processes.

JavaScript is at the heart of modern websites because it enhances the interactivity and dynamicity of web pages. 1) It allows to change content without refreshing the page, 2) manipulate web pages through DOMAPI, 3) support complex interactive effects such as animation and drag-and-drop, 4) optimize performance and best practices to improve user experience.

C and JavaScript achieve interoperability through WebAssembly. 1) C code is compiled into WebAssembly module and introduced into JavaScript environment to enhance computing power. 2) In game development, C handles physics engines and graphics rendering, and JavaScript is responsible for game logic and user interface.


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

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

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

SublimeText3 Chinese version
Chinese version, very easy to use

SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

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),
