1. i am new to this wow addon stuff, i just made a simple addon to complete simple task in raid it works fine but i want to check who has addon or not, i looked up in google but unable to find some example code.

    You can use the addon communication channel to register and send messages between instances of your addon.

    thats not good answer, please give me decent answer. i know about communication channel but it does work for people who have addon. What about who doesnt?

    If you don't like my answer you can feel free to seek answers elsewhere. Unless I missed something, I don't have an obligation to you, and your feeling of entitlement is misplaced. There is no way to tell if someone 'does not have an addon installed'. The best you can do is make your addon respond to messages using the addon communications channel. Anyone who doesn't respond within a certain period of time, you can assume they do not have the addon.

    Of course this isn't foolproof, but its about the only method you have.