how to do this?

  • Thread starter Thread starter bob
  • Start date Start date
B

bob

Hi,

I 'm a beginner in vb.net and want to know how to make the code in order to
check whether the program still may be ran, like a shareware version e.g. 30
days.

I can do it with a database, putting the date of the first start of the
program in a field, and fetching it on each next start.
But i would like to do it without database.
Something like:
dim begdat as date
begdat = date.today()
....
The problem is: how can i keep the date of the first start permanently in
the program, each time it is started? I was thinking to cookies, but i'm not
sure how to do this.

Thanks for advice.
Bob
 
The problem is: how can i keep the date of the first start permanently
in the program, each time it is started? I was thinking to cookies,
but i'm not sure how to do this.

This is a bit of a challenge - you need to store the data persistently
somewhere.

Maybe in the registry? But just make sure you encrypt the data.

Or you could do some sort of activation scheme and send the activation date
to a remote server?

There's are probably activation/licensing components out there that do this
sort of stuff already - you may want to check google for one : )
 
I think I would distribute a license text that is encrypted along with the
code and you can write to this text file the original date it is first used
then read it back everytime it's started and check the date OR you can use a
class and serialize it to a file and read it back including an initialization
variable that gets set the first time it's run.
 
You might want to check out Infralution's licensing system. It
supports evaluation periods as well as encrypted license keys. You can
get more information and download an evaluation version from:

www.infralution.com/licensing.html

Regards
Grant Frisken
Infralution
 
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