What are the methods of javascript event binding?
Binding method: 1. Use the "object.on event name = function(){code}" statement to bind; 2. Use "event source.addEventListener(event name, event processing function name, whether to capture );" statement binding; 3. Use the "onclick" attribute in the HTML tag to bind the event.
The operating environment of this tutorial: windows7 system, javascript version 1.8.5, Dell G3 computer.
1. Use the event attribute binding handler of the event source
One of the ways to separate HTML and JS is by using the event attribute binding of the event source Event processing function, the binding format is as follows:
obj.on事件名 = 事件处理函数
obj in the format is the event source object. The bound event program is usually the definition statement of an anonymous function, or a function name.
Event source event attribute binding handler example:
oBtn.onclick = function(){//oBtn为事件源对象，它的单击事件绑定了一个匿名函数定义
alert('hi')
};2. Use addEventListener() to bind the handler
addEventListener() Yes A method in the standard event model, valid in all standard browsers. The format of using addEvent Lister() to bind an event handler is as follows:
事件源.addEventListener(事件名称,事件处理函数名,是否捕获);
The parameter "event name" is an event name without "on"; the parameter "whether to capture" is a Boolean value, the default value It is false. When false, event bubbling is achieved, and when true, event capture is achieved.
By calling addEventListener() multiple times, you can bind multiple event handlers to the same event type of an event source object. When an event occurs on an object, all event handling functions bound to the event will be called and executed in sequence in the order in which they were bound. In addition, it should be noted that this in the event handling function bound by addEventListener() points to the event source.
addEventListener() binding handler example:
document.addEventListener('click',fn1,false);//click事件绑定fn1函数实现事件冒泡 document.addEventListener('click',fn2,true);//click事件绑定fn2函数实现事件捕获
3. Use the event attribute binding handler of the HTML tag
It should be noted that , when using the event attribute of an HTML tag to bind an event handler, the script code in the event attribute cannot contain a function declaration, but can be a function call or a series of script codes separated by semicolons.
Example: Bind an event handler using the event attribute of the HTML tag.
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>使用HTML标签的事件属性绑定事件处理程序</title>
</head>
<body>
<input type="button" onclick="var name='张三';alert(name);" value="事件绑定测试"/>
</body>
</html>The button in the above code is the target object of the click event, which binds two script codes for event processing through the event attribute onclick of the label. After the above code is run in the Chrome browser, when the user clicks the button, a warning dialog box will pop up.
[Recommended learning: javascript advanced tutorial]
The above is the detailed content of What are the methods of javascript event binding?. For more information, please follow other related articles on the PHP Chinese website!
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
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
How to implement an online speech recognition system using WebSocket and JavaScript
Dec 17, 2023 pm 02:54 PM
How to use WebSocket and JavaScript to implement an online speech recognition system Introduction: With the continuous development of technology, speech recognition technology has become an important part of the field of artificial intelligence. The online speech recognition system based on WebSocket and JavaScript has the characteristics of low latency, real-time and cross-platform, and has become a widely used solution. This article will introduce how to use WebSocket and JavaScript to implement an online speech recognition system.
WebSocket and JavaScript: key technologies for implementing real-time monitoring systems
Dec 17, 2023 pm 05:30 PM
WebSocket and JavaScript: Key technologies for realizing real-time monitoring systems Introduction: With the rapid development of Internet technology, real-time monitoring systems have been widely used in various fields. One of the key technologies to achieve real-time monitoring is the combination of WebSocket and JavaScript. This article will introduce the application of WebSocket and JavaScript in real-time monitoring systems, give code examples, and explain their implementation principles in detail. 1. WebSocket technology
How to implement an online reservation system using WebSocket and JavaScript
Dec 17, 2023 am 09:39 AM
How to use WebSocket and JavaScript to implement an online reservation system. In today's digital era, more and more businesses and services need to provide online reservation functions. It is crucial to implement an efficient and real-time online reservation system. This article will introduce how to use WebSocket and JavaScript to implement an online reservation system, and provide specific code examples. 1. What is WebSocket? WebSocket is a full-duplex method on a single TCP connection.
How to use JavaScript and WebSocket to implement a real-time online ordering system
Dec 17, 2023 pm 12:09 PM
Introduction to how to use JavaScript and WebSocket to implement a real-time online ordering system: With the popularity of the Internet and the advancement of technology, more and more restaurants have begun to provide online ordering services. In order to implement a real-time online ordering system, we can use JavaScript and WebSocket technology. WebSocket is a full-duplex communication protocol based on the TCP protocol, which can realize real-time two-way communication between the client and the server. In the real-time online ordering system, when the user selects dishes and places an order
JavaScript and WebSocket: Building an efficient real-time weather forecasting system
Dec 17, 2023 pm 05:13 PM
JavaScript and WebSocket: Building an efficient real-time weather forecast system Introduction: Today, the accuracy of weather forecasts is of great significance to daily life and decision-making. As technology develops, we can provide more accurate and reliable weather forecasts by obtaining weather data in real time. In this article, we will learn how to use JavaScript and WebSocket technology to build an efficient real-time weather forecast system. This article will demonstrate the implementation process through specific code examples. We
Simple JavaScript Tutorial: How to Get HTTP Status Code
Jan 05, 2024 pm 06:08 PM
JavaScript tutorial: How to get HTTP status code, specific code examples are required. Preface: In web development, data interaction with the server is often involved. When communicating with the server, we often need to obtain the returned HTTP status code to determine whether the operation is successful, and perform corresponding processing based on different status codes. This article will teach you how to use JavaScript to obtain HTTP status codes and provide some practical code examples. Using XMLHttpRequest
How to use insertBefore in javascript
Nov 24, 2023 am 11:56 AM
Usage: In JavaScript, the insertBefore() method is used to insert a new node in the DOM tree. This method requires two parameters: the new node to be inserted and the reference node (that is, the node where the new node will be inserted).
How to get HTTP status code in JavaScript the easy way
Jan 05, 2024 pm 01:37 PM
Introduction to the method of obtaining HTTP status code in JavaScript: In front-end development, we often need to deal with the interaction with the back-end interface, and HTTP status code is a very important part of it. Understanding and obtaining HTTP status codes helps us better handle the data returned by the interface. This article will introduce how to use JavaScript to obtain HTTP status codes and provide specific code examples. 1. What is HTTP status code? HTTP status code means that when the browser initiates a request to the server, the service
