JavaScript Advanced DOM Manipulation tutorial

JavaScript HTML DOM Elements

The JS DOM (Document Object Model) is an Object Model for HTML Documents. When a web page loads, the browser creates a tree like representation of the HTML document.

What You Will Learn?

• How to change the content of HTML elements.
• How to change the style CSS of HTML elements.
• How to add and delete HTML elements.
• How to react to events in from HTML elements.

HTML DOM Tree

Selecting HTML Elements

To selecting the HTML elements.

Manipulating Structure & Creating Elements

• The document.createElement() is used to create a new element in the document. You can then add this element to the document using advanced Js dom methods like appendChild() or insertBefore().

Setting Attributes & Modifying Elements

• Use setAttribute() to modify or add new attributes to elements. This is particularly useful for setting classes, ids, or data attributes.
• Besides setting attributes, you can directly change the styles, properties, or inner HTML of an element.

Removing Elements

How to remove elements from the DOM, either by using removeChild() or the more recent remove() method.

• removeChild() requires a reference to the parent node and then removes the specified child from it. The remove() is a simpler alternative that doesn’t need a reference to the parent node.

Introduction to Array Methods

Learn how to iterate over array elements using the forEach method to execute a function on each element.

• The forEach is a method that allows you to loop through each item in an array, similar to a for loop, but with cleaner syntax and better abstraction. Syntax of array to use a .forEach function element actions

Js filter Array

• The filter() method creates a new array filled with elements that pass a test provided by a function.
• The filter creates a new array including elements where the test function returns true and excluding those where it returns false. Let new Array and array.filter element condition.

JavaScript Events and Form Handling

Handling Forms with JavaScript

Validate user input forms using JavaScript and key concepts and implementation.

• Capturing User Input and utilize getElementById() and querySelector() to access input elements.

• Validating Form Input and Check the validity of form data, such as ensuring fields are not empty and email addresses are in a correct format.

JS form validation before submit the form.

After submit the html form view the result.

Prevent Default Form Behavior

How to use event.preventDefault() to stop the form from submitting in the traditional way, which allows for custom validation and handling via JavaScript.

• Use preventDefault() within an event listener to prevent the default action of a checkbox.

Form Creation and Validation

• Users will create a login or register form with fields for username, password, and email. Implement validation checks for each input and provide appropriate feedback.

Simple HTML form screenshot.