.NET own configuration file

Question

Is there any way that I could specify at runtime the configuration file I would like to use (other than App.config)? For example I would like to read a first argument from a command line that will be a path to the application's config and I would like my application to refer to it when I use ConfigurationManager.AppSettings (It's probably impossible but still it's worth asking).
I did find this piece of code:

System.Configuration.Configuration config
    = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
        config.AppSettings.File = myRuntimeConfigFilePath;
        config.Save(ConfigurationSaveMode.Modified);
        ConfigurationManager.RefreshSection("appSettings");

It works, but it overrides the original App.config's AppSettings section and my application isn't supposed to write anything.

Answer 1

I found this and it works. "path" is a path to configuration file.

AppDomain.CurrentDomain.SetData("APP_CONFIG_FILE", path);

Answer 2

Not directly.

Indirectly, you could:

• spin up a second AppDomain, specify the config-file for that (AppDomainSetup.ConfigurationFile), and execute the code in the app domain
• have two exes; the first (foo.exe) simply copies the config (into bar.exe.config) and shells the 2nd exe (bar.exe) [warning: thread race]

Answer 3

If you're using log4net you can specify your configuration file in the AssemblyInfo.cs

Answer 4

Another solution is to refactor and create your own ConfigurationRepository. Then you can change at runtime what specific repository implementation you will use.

For example, AppConfigRepository : ConfigurationRespository will just be a facade for the old ConfigurationManager.AppSettings["key"].