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JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM Using CSS Queries to Select Page Elements

Posted by Travis Sly
Travis Sly
3,947 Points

Quick confirmation

So i just had a quick question just to confirm if these two snippets have the same functionality:

So my understanding is that .getElementsByClassName('test') is essentially the same as .querySelectorAll('.test')

as well as would these two be the same?:

.querySelector('#test') & .getElementById('test')

since they both return only 1.

are there any differences between these two examples or are they the same? what applications may you use them differently if there are differences.

thank you in advance! :)

1 Answer

Peter Vann
Peter Vann
36,427 Points
Peter Vann
Peter Vann
36,427 Points

Yes, for all intents and purposes, they are virtually identical in both cases - result-wise, but there are some differences.

For more info, I Googled your question and found these:

https://careerkarma.com/blog/javascript-queryselector-vs-getelementbyid/#:~:text=Conclusion,methods%20have%20wide%20browser%20support.

https://stackoverflow.com/questions/26848289/javascript-queryselector-vs-getelementbyid

https://gomakethings.com/javascript-selector-performance/#:~:text=getElementById()%20can%20run%20about,A%20millisecond.

I hope that helps. Happy coding!