How to add an invisible header to a text file?

Question

Good morning everbody,

I would like to know if there is a possibility to add an invisible text block to a text file. It could be a header or at the bottom of the file, it does not matter.

It should work like this, I open a text file I add my normal text, and before closing the file I add the secret text. When I open it again I should be able to detect if there is any secret block that is written.

Is that doable? Is there any library that does this? I cannot find anything close to this (I work with C#)

Thanks, Eric

Answer 1

No, this is not possible. If the data is saved in a file, it can be read. Hiding of data is impossible. It is either present (and thus readable), or not.

You only option would be to encrypt your data as mikelegg has commented above.