Is it possible to use different config file on different Winform Projects at runtime?

Question

Basically I have two projects. Lets name it Project A and Project B.

Both projects are WinForm apps.

There are times that I will call forms in Project B from Project A. Since both projects have different implementation of connection strings, business layer, services, and models, these are all set under app.config per project, which have different content, of course.

In other words, Project A has its own app.config. Project B has its own app.config.

Now I want to use or rather switch app.config at runtime on my winform/winapp project. Is this possible?

The problem is that when I launch the whole solution (Project A is set as startup), the app.config of Project A is loaded. Now I want to use the app.config of Project B everytime I will call Project B winforms.

Thanks for any inputs you can provide!

The executable's configuration file needs *all* settings to run. Each project's settings section has its own namespace so you can include it in the final configuration file. — Panagiotis Kanavos, Feb 01 '17 at 12:13
You could launch both projects, an let them communicate via WCF (?) — Jens Kloster, Feb 01 '17 at 13:21
But my project is only plain winform apps. Do I need to create wcf for this? — Willy David Jr, Feb 01 '17 at 13:22
@WillyDavidJr it was a *wild* suggestion :) not an answer. Maybe you need to work with a solution that does not require you to dynamicly change configs at runtime. Perhaps Dependenci Injection can help you? — Jens Kloster, Feb 01 '17 at 13:29
No worries @JensKloster. Both projects were implemented using Independency Injection. The problem is these two projects use a different connection strings, different Data Access Layer, Services and Models which was already included on per project. Upon launch of Project A, it will already use its own connection string which were specified on its app.config, and all its related infra and assemblies. Now if I call the other project, I cannot change the Context since what was loaded was Context of Project A. — Willy David Jr, Feb 01 '17 at 13:36

score 3 · Accepted Answer · answered Mar 04 '17 at 04:33

If you want to change your config file at run time, this code works perfectly for me, first create a class which you will call to change your config file:

public abstract class AppConfig : IDisposable
{
    public static AppConfig Change(string path)
    {
        return new ChangeAppConfig(path);
    }

    public abstract void Dispose();

    private class ChangeAppConfig : AppConfig
    {
        private readonly string oldConfig =
            AppDomain.CurrentDomain.GetData("APP_CONFIG_FILE").ToString();

        private bool disposedValue;

        public ChangeAppConfig(string path)
        {
            AppDomain.CurrentDomain.SetData("APP_CONFIG_FILE", path);
            ResetConfigMechanism();
        }

        public override void Dispose()
        {
            if (!disposedValue)
            {
                AppDomain.CurrentDomain.SetData("APP_CONFIG_FILE", oldConfig);
                ResetConfigMechanism();


                disposedValue = true;
            }
            GC.SuppressFinalize(this);
        }

        private static void ResetConfigMechanism()
        {
            typeof(ConfigurationManager)
                .GetField("s_initState", BindingFlags.NonPublic |
                                         BindingFlags.Static)
                .SetValue(null, 0);

            typeof(ConfigurationManager)
                .GetField("s_configSystem", BindingFlags.NonPublic |
                                            BindingFlags.Static)
                .SetValue(null, null);

            typeof(ConfigurationManager)
                .Assembly.GetTypes()
                .Where(x => x.FullName ==
                            "System.Configuration.ClientConfigPaths")
                .First()
                .GetField("s_current", BindingFlags.NonPublic |
                                       BindingFlags.Static)
                .SetValue(null, null);
        }
    }
}

Then to call the this on your program, you can do this:

 using (AppConfig.Change(@"D:\app.config"))
        {
           //TODO:
        }

score -1 · Answer 2 · edited May 23 '17 at 11:46

-1

Your question has been previously asked:

Use the 'Add Existing Item' menu from Visual Studio's Solution Explorer, to add a link to the app.config in the first project. The details are given in this link:

How to Share App.config?

edited May 23 '17 at 11:46

Community

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1

answered Feb 01 '17 at 12:09

Dave S

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That's not what the question is about. It doesn't help at all – Panagiotis Kanavos Feb 01 '17 at 12:11

Is it possible to use different config file on different Winform Projects at runtime?

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