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

Posted by ammarkhan
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ammarkhan
Front End Web Development Techdegree Student 21,661 Points

What is prevLi or previous sibling?

i am confused over the syntax of 

var insertedNode = parentNode.insertBefore(newNode, referenceNode);

as in the video it guil add parameters to be (li, PrevLi). I understand the LI is what is needed to insert it before and what is the referenceNode

1 Answer

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

The referenceNode is where the insert should happen.

In your example above, the argument you supply for referenceNode will be a node that is already part of the document where you want the new node to be inserted. After the insertBefore, the new node will be where the referenceNode was originally, and the referenceNode will now come after it.