Doc.doc umentelement. scrolltop & Doc. Body. scrolltop

Doc = document;

Doc.doc umentelement. scrolltop, Doc. Body. scrolltop

 

Scrolltop refers to the height of the object to be rolled. On the body object, it refers to the height of the window to be rolled by the scroll bar. If it is on another object, it is the height of the container to be rolled by the scroll bar.

In fact, doc.doc umentelement. scrolltop and Doc. Body. scrolltop indicate the height of the window to be rolled by the scroll bar. So why are there two more?

Nature:

If the page has a DTD (or doctype specified), use document.doc umentelement.

If the page does not have a DTD (or doctype is not specified), use document. Body.

 

Common Compatibility: scrolltop = doc.doc umentelement. scrolltop | Doc. Body. scrolltop;