Creating nodes in html

How To Make Changes to the DOM

In the previous two installments of the Understanding the DOM series, we learned How To Access Elements in the DOM and How To Traverse the DOM. Using this knowledge, a developer can use classes, tags, ids, and selectors to find any node in the DOM, and use parent, child, and sibling properties to find relative nodes.

The next step to becoming more fully proficient with the DOM is to learn how to add, change, replace, and remove nodes. A to-do list application is one practical example of a JavaScript program in which you would need to be able to create, modify, and remove elements in the DOM.

In this tutorial, we will go over how to create new nodes and insert them into the DOM, replace existing nodes, and remove nodes.

Creating New Nodes

In a static website, elements are added to the page by directly writing HTML in an .html file. In a dynamic web app, elements and text are often added with JavaScript. The createElement() and createTextNode() methods are used to create new nodes in the DOM.

Property/Method	Description
createElement()	Create a new element node
createTextNode()	Create a new text node
node.textContent	Get or set the text content of an element node
node.innerHTML	Get or set the HTML content of an element

To begin, let’s create an index.html file and save it in a new project directory.

DOCTYPE html> html lang="en"> head> title>Learning the DOMtitle> head> body> h1>Document Object Modelh1> body> html> 

Right click anywhere on the page and select “Inspect” to open up Developer Tools, then navigate to the Console.

We will use createElement() on the document object to create a new p element.

We’ve created a new p element, which we can test out in the Console.

The paragraph variable outputs an empty p element, which is not very useful without any text. In order to add text to the element, we’ll set the textContent property.

Output
I'm a brand new paragraph.
 

A combination of createElement() and textContent creates a complete element node.

An alternate method of setting the content of the element is with the innerHTML property, which allows you to add HTML as well as text to an element.

Note: While this will work and is a common method of adding content to an element, there is a possible cross-site scripting (XSS) risk associated with using the innerHTML method, as inline JavaScript can be added to an element. Therefore, it is recommended to use textContent instead, which will strip out HTML tags.

It is also possible to create a text node with the createTextNode() method.

With these methods, we’ve created new elements and text nodes, but they are not visible on the front end of a website until they’ve been inserted into the document.

Inserting Nodes into the DOM

In order to see the new text nodes and elements we create on the front end, we will need to insert them into the document . The methods appendChild() and insertBefore() are used to add items to the beginning, middle, or end of a parent element, and replaceChild() is used to replace an old node with a new node.

Property/Method	Description
node.appendChild()	Add a node as the last child of a parent element
node.insertBefore()	Insert a node into the parent element before a specified sibling node
node.replaceChild()	Replace an existing node with a new node

To practice these methods, let’s create a to-do list in HTML:

ul> li>Buy groceriesli> li>Feed the catli> li>Do laundryli> ul> 

When you load your page in the browser, it will look like this:

In order to add a new item to the end of the to-do list, we have to create the element and add text to it first, as we did in the “Creating New Nodes” section above.

Now that we have a complete element for our new to-do, we can add it to the end of the list with appendChild() .

You can see the new li element has been appended to the end of the ul .

ul> li>Buy groceriesli> li>Feed the catli> li>Do laundryli> li>Do homeworkli> ul> 

Maybe we have a higher priority task to do, and we want to add it to the beginning of the list. We’ll have to create another element, as createElement() only creates one element and cannot be reused.

We can add it to the beginning of the list using insertBefore() . This method takes two arguments — the first is the new child node to be added, and the second is the sibling node that will immediately follow the new node. In other words, you’re inserting the new node before the next sibling node. This will look similar to the following pseudocode:

parentNode.insertBefore(newNode, nextSibling); 

For our to-do list example, we’ll add the new anotherTodo element before the first element child of the list, which is currently the Buy groceries list item.

ul> li>Pay billsli> li>Buy groceriesli> li>Feed the catli> li>Do laundryli> li>Do homeworkli> ul> 

The new node has successfully been added at the beginning of the list. Now we know how to add a node to a parent element. The next thing we may want to do is replace an existing node with a new node.

We’ll modify an existing to-do to demonstrate how to replace a node. The first step of creating a new element remains the same.

Like insertBefore() , replaceChild() takes two arguments — the new node, and the node to be replaced, as shown in the pseudocode below.

parentNode.replaceChild(newNode, oldNode); 

We will replace the third element child of the list with the modified to-do.

ul> li>Pay billsli> li>Buy groceriesli> li>Feed the dogli> li>Do laundryli> li>Do homeworkli> ul> 

With a combination of appendChild() , insertBefore() , and replaceChild() , you can insert nodes and elements anywhere in the DOM.

Removing Nodes from the DOM

Now we know how to create elements, add them to the DOM, and modify existing elements. The final step is to learn to remove existing nodes from the DOM. Child nodes can be removed from a parent with removeChild() , and a node itself can be removed with remove() .

Using the to-do example above, we’ll want to delete items after they’ve been completed. If you completed your homework, you can remove the Do homework item, which happens to be the last child of the list, with removeChild() .

ul> li>Pay billsli> li>Buy groceriesli> li>Feed the dogli> li>Do laundryli> ul> 

Another method could be to remove the node itself, using the remove() method directly on the node.

ul> li>Pay billsli> li>Feed the dogli> li>Do laundryli> ul> 

Between removeChild() and remove() , you can remove any node from the DOM. Another method you may see for removing child elements from the DOM is setting the innerHTML property of a parent element to an empty string ( «» ). This is not the preferred method because it is less explicit, but you might see it in existing code.

Conclusion

In this tutorial, we learned how to use JavaScript to create new nodes and elements and insert them into the DOM, and replace and remove existing nodes and elements.

At this point in the Understanding the DOM series you know how to access any element in the DOM, walk through any node in the DOM, and modify the DOM itself. You can now feel confident in creating basic front-end web apps with JavaScript.

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Tutorial Series: Understanding the DOM — Document Object Model

The Document Object Model, usually referred to as the DOM, is an essential part of making websites interactive. It is an interface that allows a programming language to manipulate the content, structure, and style of a website. JavaScript is the client-side scripting language that connects to the DOM in an internet browser.

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Mastering HTML DOM Manipulation: A Guide to Creating New Nodes in JavaScript using Node.js

Learn how to create new nodes in JavaScript for HTML DOM manipulation using createElement(), insertBefore(), createTextNode(), and Object.create() methods. Discover best practices, common issues, and how to use Node.js for web development and file management.

• Creating an element node using createElement() method
• Inserting a new node before an existing node with insertBefore() method
• How to create a new Node.js project [6 of 26]
• Creating a text node with createTextNode() method
• Creating a new object with Object.create() method
• Creating a web server in Node.js with the HTTP module
• Creating a Node.js project
• Other helpful code examples for creating a new node in JavaScript
• Conclusion
• How to create a new node in JavaScript?
• How do you create a first node?
• How do I create a node JS page in HTML?
• How to create a new div in JavaScript?

JavaScript is a popular language for web development, and creating new nodes is essential for manipulating the HTML DOM. In this post, we will discuss the key points and methods for creating a new node in JavaScript, as well as best practices and common issues. We will also cover how to use Node.js for web development and file management.

Creating an element node using createElement() method

The createElement() method creates a new element node in JavaScript. To create a new DOM node, use document.createElement(tagName) . For example, the following code creates a new div element node:

let newDiv = document.createElement('div'); 

The createElement() method is commonly used to create new nodes in the HTML DOM. You can also use it to create new nodes for XML documents.

Inserting a new node before an existing node with insertBefore() method

The Node.insertBefore() method inserts a node as a child, right before an existing child, which you specify. If the given child is a reference to an existing node in the document, appendChild() moves it from its current position to the new position.

For example, the following code inserts a new li element node before the existing li element node:

let parentElement = document.getElementById('myList'); let newElement = document.createElement('li'); let referenceElement = document.getElementsByTagName('li')[0]; parentElement.insertBefore(newElement, referenceElement); 

How to create a new Node.js project [6 of 26]

Demonstration: quickly initialize new Node.js project using the NPM CLI.Full «Intro to Node.js Duration: 3:36

Creating a text node with createTextNode() method

The createTextNode() method creates a new text node in JavaScript. For example, the following code creates a new text node with the text “Hello World»:

let text = document.createTextNode('Hello World'); 

You can then append this text node to an existing element node using the appendChild() method.

Creating a new object with Object.create() method

The Object.create() method creates a new object with the specified prototype object and properties. For example, the following code creates a new object with no properties:

let newObj = Object.create(null); 

This method is commonly used to create objects with specific prototypes and properties.

Creating a web server in Node.js with the HTTP module

The HTTP module can be used to create a web server in Node.js. You can add a request listener function to handle incoming requests. For example, the following code creates a web server that responds with the text “Hello World!” to all requests:

const http = require('http');http.createServer(function (req, res) < res.writeHead(200, ); res.end('Hello World!'); >).listen(8080); 

Creating a Node.js project

To create a Node.js project, you need to go to the NodeJS website, download NodeJS, ensure Node and NPM are installed and their PATHs defined. Then, create a new package.json file using npm init . For example:

This command will create a new package.json file that contains information about your project, such as its name, version, and dependencies.

Other helpful code examples for creating a new node in JavaScript

In Javascript case in point, code for adding new elements in javascriipt js code example

In Html , for example, create node in javascript code example

In Javascript , in particular, Creating Node in javascript code example

class Node < constructor(value)< this.value = value; this.next = null; >> class Stack< constructor()< this.top = null; this.bottom = null; this.length = 0; >; peek()< return this.top; >; push(value) < const newNode = new Node(value); newNode.next = this.top this.top = newNode; if(this.length === 0) this.bottom = newNode; this.length++; >pop() < if(!this.top) return; if(this.top === this.bottom)< this.top = null; this.bottom = null; this.length--; return >const temp = this.top this.top = temp.next this.length--; > >const a = new Stack();

Conclusion

Creating a new node in JavaScript is essential for manipulating the HTML DOM. The createElement() , insertBefore() , createTextNode() , and Object.create() methods can be used to create new nodes. The HTTP module can be used to create a web server in Node.js. Best practices for JavaScript include following proper syntax and naming conventions, writing reusable and modular code, and testing thoroughly. Common issues with creating new nodes in JavaScript include incorrect syntax, undefined variables, and incorrect placement of nodes. Learning how to use Node.js can be beneficial for building scalable web applications and managing files.

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