I created a PDF school book for students.
The students buy the book on my site.
The student can enter answers for homework in the book and send them to the teacher.
On the first page he enters:
- teachers email
- teachers name
- students email
- students name
and saves the pdf
with thees fields the book knows where to send the answers
The teacher can then send back the grade.
All works with FDF files.
I need to prevent students to just copy the book and not buy it?
What is the way to do this?
There is absolutely no way.
You can consider DRM (Digital Rights Management) but this is likely to be out of budget. DRM does not stop a file from being copied, but makes the copy useless.
Probably the best solution is to consider a server solution to stamp the student's name into the book. But that probably won't stop most of them.