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

Jinjia Lin
Jinjia Lin
11,942 Points
Posted by Jinjia Lin
Jinjia Lin
11,942 Points

Why is "up" and "remove" not in upper case? (like "BUTTON"?)

when we use event.target.tagName, we have to put it in caps?

but why is it not the case for event.target.className?

Thank you for enlightening me.

1 Answer

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

Tag names are stored internally in upper case, so they must always be compared with all upper case to match.

But class names are stored exactly as they are used in the code, so they must be compared with the same case.