Parameters
- rowIndex
- Index of the top row in the comment.
- colIndex
- Index of the left column in the comment.
- author
- The author of the comment.
- text
- The text of the comment.
- toRtf
- Flag indicating whether to convert author and text to RTF format.
Return Value
A reference to the object if it was successfully added to the collection, or null if the object could not be added to the collection (usually because it overlaps another comment already in the collection).