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JavaScript DOM Scripting By Example Editing and Filtering Names States of the Application

Nicholas Wallen
Nicholas Wallen
12,278 Points

Within the ul event listener, why is li referred to as a parent of ul? Isn't it the opposite?

ul.addEventListener('click', (e) => {

if (e.target.tagName === 'BUTTON') {

const button = e.target;

const li = button.parentNode;

const ul = li.parentNode;

4 Answers

From what you posted it looks like li is the parent of button and ul is the parent of li.

Othneil Drew
Othneil Drew
22,421 Points

"parentNode" is telling the browser to traverse the DOM to get the parent of the selected element.

const li = button.parentNode is finding the parent of the button and setting the li value to the button's parent. In this case the li element.

const ul = li.parentNode if finding the parent of the button and setting the ul value to the li's parent. In this case the ul element.

Andrew Tiller
Andrew Tiller
4,182 Points

<ul> is an "Unordered List" of <li> "List Items" which contain <button>s. button.parentNode will return the <li> the <button> is in. li.parentnode will return the <ul> that the <li> is in.

[element].parentNode doesn't assign something as a parent, it returns the parent of that element.

Michael Kristensen
Michael Kristensen
Full Stack JavaScript Techdegree Student 22,413 Points

button.parentNode is you asking for 'the parent of this button', and li.parentNode is you asking for 'the parent of this list item', so as written the behaviour is as you are describing; ul is the parent of li, who in turn is the parent of button.