I want to write a program that will encrypt an entire folder and it’s sub-folders, I have no problem doing this but I would like to make the entire encryption process rather transparent by letting a user double click it and have it open as if it weren’t encrypted, say if it were a picture or a word document and it’d open in it’s respective application.
How can a running program of mine become notified about the opening of a target file, stop the file from opening, do what it needs to do (decrypt), followed by running the resulting decrypted file.
How can I watch a file and do this in C#? Can I watch for other interactions like the user copying a watched file (since it won’t be in a watched folder, it should be decrypted i.e. it’s dragged to a USB device), or for deleting a watched file (say if I want to shred a file before deletion)?
P.S. The FileSystemWatcher doesn’t quite meet my needs. EDIT: What I mean is that FileSystemWatcher will tell me when a file is being opened, deleted and all those events, but it won’t let me step in real quick, decrypt the file, and hand it back to the process that normally opens that file.
You can rename files, add them your own extension, like thepicture.jpg.encrypted. Set your program as a default program for this extension and handle opening them