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JavaScript JavaScript and the DOM (Retiring) Making Changes to the DOM Getting and Setting Text with textContent and innerHTML

Why 'p.description'?

const p = document.querySelector('p.description');

Could someone help me understand what the 'p.description' means?

'description' is a class, so the dot notation makes sense. I'm confused why it needs to be preceded by a 'p', though.

(code is from the video)


<!DOCTYPE html>
    <title>JavaScript and the DOM</title>
    <link rel="stylesheet" href="css/style.css">
    <h1 id="myHeading">JavaScript and the DOM</h1>
    <p>Making a web page interactive</p>

    <p class=description>Things that are purple:</p>
    <input type="text" class="description">
    <button class="description">Change List Description</button>
    <script src="app.js"></script> 


const input = document.querySelector('input');
const p = document.querySelector('p.description');
const button button = document.querySelector('button');

button.addEventListener ('click', ()=> {
   p.textContent = input.value + ':';

2 Answers

Because there are also an input and a button elements with class description directly below the p element with class description, and you only want to select the p element with class description for that particular code.

Ah got it. So if I wanted to select all elements with the class description, then I'd use this instead? (obv it wouldn't work with the code from the class, but I just want to understand)



Thanks Joseph Yhu !