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

Nikola Jankovic
Nikola Jankovic
10,793 Points
Posted by Nikola Jankovic
Nikola Jankovic
10,793 Points

Why this alternative solution won't work?

I am just curious why this code instead of the one in the video won't work?

if (event.target.className=== "up" && event.target.parentNode !== listUl.firstChild) {  
        let li = event.target.parentNode;
        let previousLi= li.previousElementSibling;
        let ul = li.parentNode;
        ul.insertBefore(li, previousLi);
    }

1 Answer

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

The "firstChild" might not be an element, which would interfere with your test.

Try using "firstElementChild" instead.

Nikola Jankovic
Nikola Jankovic
10,793 Points
Nikola Jankovic
Nikola Jankovic
10,793 Points

Yeah, that solves it. Thanks!