App.config in CRM plugin

Hi Friends,

I got a requirement to have a app.config file in plugin class libraray.This app.config file is used to retrieve the key value and process the application .

My question are:

1) Can we have app.config file.

2) If not where could I keep the key value so that no need to build the app every time.

3) If we could have the app.config file, then how to work with it.

Please suggest me.

Thanks in Advance,

Datta.G