What is querySelector in JavaScript ?

What is querySelector in JavaScript

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Understanding querySelector

The querySelector method is a built-in JavaScript function that allows you to select the first element in the DOM that matches a specified CSS selector. This method provides a more flexible and concise way to target elements compared to older methods like getElementById, getElementsByClassName, or getElementsByTagName.

Syntax:

document.querySelector(selector);

• selector: A string containing a CSS selector that specifies the element(s) you want to select. This could be an ID, class, tag, or any valid CSS selector.

The querySelector method returns the first element that matches the selector. If no elements match, it returns null.

Example 1: Selecting an Element by ID

One of the simplest uses of querySelector is selecting an element by its ID.

Example:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>querySelector by ID</title>
    <script>
        document.addEventListener("DOMContentLoaded"…