.net – Accessing the settings (app.config) of the calling application

app-confignetsettingsvisual studio

I have a WinForms application ("WF"), and a Library called by that WinForms application ("LIB")

WF has a Settings.settings (Visual Studio Designer) and app.config combo. I gather than the designer is a front end that auto generates the app.config file. To use those settings from within WF, I use the strongly typed properties of the class it autogenerates (i.e. WF.Settings.MyTimeOutSetting).

When WF calls a method in LIB, I want to use one of WF's settings from within lib. How can I retrieve a setting from the caller's (WF's) app.config while in the callee's (LIB's) code?

Best Answer

Like John said, this is a bad idea. The caller (exe in this case) should pass the needed information to the DLL. That way you can re-use the DLL later, somewhere else, and not have some 'invisible' dependency on an app.config setting.

Try this:

Dim oConfiguration As System.Configuration.Configuration
oConfiguration = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None)
Dim sValue As String = oConfiguration.AppSettings.Settings("setting").Value

Related Solutions

C# – the difference between String and string in C#

string is an alias in C# for System.String.
So technically, there is no difference. It's like int vs. System.Int32.

As far as guidelines, it's generally recommended to use string any time you're referring to an object.

e.g.

string place = "world";

Likewise, I think it's generally recommended to use String if you need to refer specifically to the class.

e.g.

string greet = String.Format("Hello {0}!", place);

This is the style that Microsoft tends to use in their examples.

It appears that the guidance in this area may have changed, as StyleCop now enforces the use of the C# specific aliases.

C# – Calling the base constructor in C#

Modify your constructor to the following so that it calls the base class constructor properly:

public class MyExceptionClass : Exception
{
    public MyExceptionClass(string message, string extrainfo) : base(message)
    {
        //other stuff here
    }
}

Note that a constructor is not something that you can call anytime within a method. That's the reason you're getting errors in your call in the constructor body.

Best Answer

Related Solutions

C# – the difference between String and string in C#

This is the style that Microsoft tends to use in their examples.

C# – Calling the base constructor in C#

Related Topic