ASP.NET web controls - how to make evaluation or trial version?

Question

I had to develop some custom ASP.NET web controls because I couldn't find ones already available for purchase with the functionality required. I was surprised I couldn't find what I needed and I'm thinking the web controls I developed may be useful to others.

So I'm thinking maybe I can sell my newly developed web controls and make a buck. I realize I could make them open source and ask for donations, but for reasons I don't want to go into here, I'd rather make an evaluation/trial version and then require folks to purchase a license if they way to use them longer than the trial period.

I've never even though about how to make a trial version of software. Seems that anything I come up with could easily be thwarted by any competent .NET developer by using one of the available .NET decompilers.

Can anyone give some pointers, references (web pages, books, etc.) that touch on how evaluation/trial versions of software are implemented?

Answer 1

Here is some documentation on the ASP.NET Server Control Licensing pattern:

http://msdn.microsoft.com/en-us/library/aa479017.aspx

Any competent developer will be able to thwart protections. It is not worth your time creating licensing that is a burden to your honorable customers just to make it "harder" for the dishonorable ones who will get around it regardless.

What you want is something that stops a casual developer from just installing and never thinking about having to paste a license key somewhere. As long as there is some tiny reminder to keep honorable people honorable, thats all you want.