Question

When your web.config or app.config file has an appsettings entry, what is the best way to refer to its key in your code file?

Developers I have worked with have differing opinions on this. Some say to hard code the string and others suggest that there should be a file containing string constants and in your code, you use the constant as the appsettings key.

I would be interested in hearing other opinions on this. What do you do? Why is it the best?

Answer 1

Skip the string constants, and create a configuration wrapper class instead.

class MyConfiguration
{
    public static string SomeConfigValue
    {
        get
        {
            return WebConfigurationManager.AppSettings["SomeConfigValue"];
        }
    }

    public static int SomeOtherConfigValue
    {
        get
        {
            return int.Parse(WebConfigurationManager.AppSettings["SomeOtherConfigValue"];
        }
    }

    //..and so on
}

Then you could get it like this:

string s = MyConfiguration.SomeConfigValue;
int i = MyConfiguration.SomeOtherConfigValue;

(You might consider not going the static route if you want to remove dependencies on the configuration system while unittesting)