A comment added to a certain portion in a first document can be automatically re-added to an equivalent position in a second document, and comment transfer processing between documents is automatically performed. Position information of a comment with respect to an old document obtained from an old document comment file is stored in a position information area, and comment contents also obtained from the old document comment file are stored in a comment content area. A character string corresponding to the position information is extracted from an old document file, and is stored in a character string area. A new document file is searched on the basis of the character string stored in the character string area, and position information of the detected character string is stored in a candidate area. One of position information stored in the candidate area is selected according to a predetermined rule, and the selected position information is stored in a new position information area. The comment contents stored in the comment content area, and the position information stored in the new position information area are written in a new document comment file.
展开▼