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JavaScript JavaScript and the DOM Making Changes to the DOM Set Inline Styles with the style Property

why .document.getElementsByClassName(' ') instead of document.querySelector('. ') doesnt work? console shows a mistake

why .document.getElementsByClassName(' ') instead of document.querySelector('. ') doesnt work? console shows a mistake addEventListener is not a function, but when I CHANGE it to queryselector everything works as it should?

1 Answer

Steven Parker
Steven Parker
230,274 Points

One major difference between these functions is that querySelector returns a reference to a single element, but getElementsByClassName returns an element collection (which is like an array).