Find Line Above or Below in Javascript

Question

I am working on an in-place HTML editor, concentrating on Firefox only right now. I have an element inserted where the cursor should be and also have left and right arrows working, but I can't seem to find a way to find:

1. Start and end of a line for the home and end keys
2. The next line up or down for the up/down arrows.

I see document.elementFromPoint, but this doesn't get me a Range object. The Range object itself seems rather useless when it comes to using pixel positions.

Answer 1

If you need a to create a range for the element under specific pixel position, you can combine document.elementFromPoint() and document.createRange() and Range.selectNodeContents();

The snippet below would highlight the content of an element at (100,200)

var elem = document.elementFromPoint(100,200);
var r = document.createRange();
var s = window.getSelection()
r.selectNodeContents(elem);
s.removeAllRanges();
s.addRange(r);

I hope this will help you find the final solution.