Web Front-endJS TutorialDetailed explanation of how to create, use and delete dom node instances in JavaScript
Create node
In order to create a new node, you can use createElement and createTextNode. If the new creation is completed, you can use appendChild() to add the node to the DOM tree.
Create an element P and set the innerHTML attribute
var myp = document.createElement('p'); myp.innerHTML = 'yet another';
After the element P is created, you can modify and add attributes at will
myp.style.border = '2px dotted blue'
Next, you can use appendChild to add new nodes to the DOM tree.
document.body.appendChild(myp)
Methods of using DOM
It is indeed very simple to use the innerHTML method. We can use the pure dom method to achieve the above functions.
Create a new text node (yet another)
Create a new paragraph
Place the text node Add to paragraph.
Add paragraphs to body
// 创建p var myp = document.createElement('p'); // 创建一个文本节点 var myt = document.createTextNode('one more paragraph') myp.appendChild(myt); // 创建一个STRONG元素 var str = document.createElement('strong'); str.appendChild(document.createTextNode('bold')); // 把STRONG元素添加到P中 myp.appendChild(str); // 把P元素添加到BODY中 document.body.appendChild(myp); //结果<p>one more paragraph<strong>bold</strong></p> cloneNode()
Another way to create a new node is, we You can use cloneNode to copy a node. cloneNode() can pass in a boolean parameter. If true, it means a deep copy, including its child nodes, if false, it only copies itself.
First get the element to be copied.
var el = document.getElementsByTagName('p')[1];//<p><em>second</em> paragraph</p>
No need to make a deep copy first.
document.body.appendChild(el.cloneNode(false))
We found that the page did not change, because only the element p was copied. The same effect as below.
document.body.appendChild(document.createElement('p'));
If deep copy is used, all child nodes including p below will be copied. Including text nodes and EM elements of course.
document.body.appendChild(el.cloneNode(true))
insertBefore()
Using appendChild is to add the element to the end. The insertBefore method can more precisely control the position of inserted elements.
elementNode.insertBefore(new_node,existing_node)
Example
document.body.insertBefore( document.createTextNode('boo!'), document.body.firstChild );
It means to create a new text node and use it as the first node of the body element .
Delete Node
To delete a node from the DOM tree, we can use removeChild(). Let’s take a look at the HTML to be operated
<body> <p class="opener">first paragraph</p> <p><em>second</em> paragraph</p> <p id="closer">final</p> <!-- and that's about it --> </body>
Let’s take a look at the following code. Delete the second paragraph
var myp = document.getElementsByTagName('p')[1]; var removed = document.body.removeChild(myp);
The removed node is the deleted node. The deleted node can still be used in the future.
We can also use the replaceChild() method. This method is to delete a node and replace it with another node. After performing the last node deletion operation, the result is as follows
<body> <p class="opener">first paragraph</p> <p id="closer">final</p> <!-- and that's about it --> </body>
Let’s take a look at the use of replaceChild. We replace the second p
var replaced = document.body.replaceChild(removed, p);
with the last deleted node, which is the same as removeChild returns. Replaced is the removed node. Now the result is
<body> <p class="opener">first paragraph</p> <p><em>second</em> paragraph</p> <!-- and that's about it --> </body>
The above is the detailed content of Detailed explanation of how to create, use and delete dom node instances in JavaScript. For more information, please follow other related articles on the PHP Chinese website!
es6数组怎么去掉重复并且重新排序May 05, 2022 pm 07:08 PM去掉重复并排序的方法：1、使用“Array.from(new Set(arr))”或者“[…new Set(arr)]”语句，去掉数组中的重复元素，返回去重后的新数组；2、利用sort()对去重数组进行排序，语法“去重数组.sort()”。
JavaScript的Symbol类型、隐藏属性及全局注册表详解Jun 02, 2022 am 11:50 AM本篇文章给大家带来了关于JavaScript的相关知识，其中主要介绍了关于Symbol类型、隐藏属性及全局注册表的相关问题，包括了Symbol类型的描述、Symbol不会隐式转字符串等问题，下面一起来看一下，希望对大家有帮助。
原来利用纯CSS也能实现文字轮播与图片轮播！Jun 10, 2022 pm 01:00 PM怎么制作文字轮播与图片轮播？大家第一想到的是不是利用js，其实利用纯CSS也能实现文字轮播与图片轮播，下面来看看实现方法，希望对大家有所帮助！
JavaScript对象的构造函数和new操作符（实例详解）May 10, 2022 pm 06:16 PM本篇文章给大家带来了关于JavaScript的相关知识，其中主要介绍了关于对象的构造函数和new操作符，构造函数是所有对象的成员方法中，最早被调用的那个，下面一起来看一下吧，希望对大家有帮助。
JavaScript面向对象详细解析之属性描述符May 27, 2022 pm 05:29 PM本篇文章给大家带来了关于JavaScript的相关知识，其中主要介绍了关于面向对象的相关问题，包括了属性描述符、数据描述符、存取描述符等等内容，下面一起来看一下，希望对大家有帮助。
javascript怎么移除元素点击事件Apr 11, 2022 pm 04:51 PM方法：1、利用“点击元素对象.unbind("click");”方法，该方法可以移除被选元素的事件处理程序；2、利用“点击元素对象.off("click");”方法，该方法可以移除通过on()方法添加的事件处理程序。
整理总结JavaScript常见的BOM操作Jun 01, 2022 am 11:43 AM本篇文章给大家带来了关于JavaScript的相关知识，其中主要介绍了关于BOM操作的相关问题，包括了window对象的常见事件、JavaScript执行机制等等相关内容，下面一起来看一下，希望对大家有帮助。
foreach是es6里的吗May 05, 2022 pm 05:59 PMforeach不是es6的方法。foreach是es3中一个遍历数组的方法，可以调用数组的每个元素，并将元素传给回调函数进行处理，语法“array.forEach(function(当前元素,索引,数组){...})”；该方法不处理空数组。
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
EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function
Dreamweaver CS6
Visual web development tools
WebStorm Mac version
Useful JavaScript development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
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
