How do I query editor contents?

How can I programmatically query editor contents? I tried going off of http://docs.cksource.com/ckeditor_api/symbols/CKEDITOR.editor.html#getData, but "editor1", "editor0", and "scratchpad" (the HTML ID of the TEXTAREA) were all empty.

(See http://stackoverflow.com/questions/21142519/how-do-i-programmatically-query-ckeditor-contents for an attempt that includes jQuery.)