Determine on which row of textarea is the cursor

Question

How to determine on which row of textarea is the cursor with javascript?

Answer 1

I think it will involve fiddly calculations with font sizes, padding, borders, margins, and line breaks. I expect it'll be hard to get it right in the general case. You could take a look at the source code of the following, which displays an autocomplete dialog as you type in a textarea. It was posted on Ajaxian recently and does what you need to do: http://media.chikuyonok.ru/content-assist/