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JavaScript JavaScript and the DOM (Retiring) Traversing the DOM Using previousElementSibling and insertBefore

What is an element sibling?

I don't quite understand what an element sibling is?

Sibling elements are elements that share the same parent. For example all of the <li> within a <ul> would be siblings of each other.

<ul class="parent">
  <li>sibling</li> 
  <li>sibling</li>
  <li>sibling</li>
</ul>

Hope this helps!

Thanks a lot! This helped me a lot!

Does previousSibling exist that is used in the video?

2 Answers

Steven Parker
Steven Parker
229,788 Points

A "sibling" is any other element that is in the same container. For example, all the option elements inside a select are siblings.

The "previousSibling" is the sibling that comes just before the current item. Note that this is a node-based term so you may prefer to use "previousElementSibling" instead in most cases. This guarantees a reference to another element and not something like a text node.

Theres another part of the video where I don't understand.

let li = event.target.parentNode; let ul = li.parentNode; ul.removeChild(li);
Isn't <li> meant to be a child node? I don't quite understand this part? ---> let li = event.target.parentNode;

Steven Parker
Steven Parker
229,788 Points

The <li> is both a parent and child. It's a child of the <ul>, but it's the parent to the element that caused the event. That element is inside the <li>.