Question

Do you prefer reading parameters in a configuration file at one place and pass them as a parameter to modules/functions or read them as and when required?

Answer 1

Yes, I strongly prefer passing them in as parameters and it’s not close. The System.Configuration classes should never never never pervade into your classes beyond setting up the application root.

1. By passing them as parameters, you make dependencies explicit.
2. You avoid having your domain classes be dependent on System.Configuration.
3. If you don’t pass them in as parameters (but instead read them when/where needed), you are violating SRP.
4. If you don’t pass them in as parameters (but instead read them when/where needed), you make testing difficult.
5. If you don’t pass them in as parameters (but instead read them when/where needed), you have increased your maintenance costs.