Question

I’m trying to call a custom action within my Setup & Deployment project to update some items within the app.config on my app. I’ve wrapped up the custom config section in the usual way, e.g.:

[ConfigurationProperty("serviceProvider", IsRequired = true)]
public string ServiceProvider
{
    get { return (string)base["serviceProvider"]; }
    set { base["dataProviderFactory"] = value; }
}

I’ve set the custom action to be called during the Install section of installation just after base.Install(stateSaver). The code is:

string exePath = string.Format("{0} MyApp.exe", Context.Parameters["DP_TargetDir"]);
SysConfig.Configuration config = ConfigurationManager.OpenExeConfiguration(exePath);
Configuration. MyApp section = Configuration.MyApp)config.GetSection("MyApp");

When I run this, I get this error:

System.Configuration.ConfigurationErrorsException: An error occurred creating the configuration section handler for MyApp: Could not load file or assembly ‘MyCompany. MyApp.Configuration’ or one of its dependencies. The system cannot find the file specified. (C:\Program Files\MyCompany\MyApp\MyApp.exe.config line 5) —> System.IO.FileNotFoundException: Could not load file or assembly ‘MyCompany.MyApp.Configuration’ or one of its dependencies. The system cannot find the file specified.

Line 5 in the config is:

<section name="MyApp"
    type="MyCompany.MyApp.Configuration.MyApp, MyCompany.MyApp.Configuration"
    requirePermission="false" />

The class library with the installer code (that being the only class in that library) has a reference to the config assembly.

Is there something really obvious that I’m missing here? I can’t work out why the ref to the config isn’t being found.

Any help/suggestions would be very much appreciated.

Answer 1

I managed to find some code on MSDN that provides a working (albeit hacked) way to do this. Link is here: ConfigurationManager, custom config, and installutil / path searching problem.

Wouldn’t have found it if not for being able to debug with help from suggestions so thanks to both of you for that.

For reference, my final install code is:

public override void Install(IDictionary stateSaver)
{
    base.Install(stateSaver);

    string targetDirectory = Context.Parameters["DP_TargetDir"];
    stateSaver.Add("TargetDir", targetDirectory);

    string exePath = Path.Combine(targetDirectory, "MyApp.exe");

    System.Diagnostics.Debugger.Break();

    ResolveEventHandler tempResolveEventHandler =
        (sender, args) =>
            {
                string simpleName = new AssemblyName(args.Name).Name;
                string path = Path.Combine(targetDirectory, simpleName + ".dll");
                return File.Exists(path)
                    ? Assembly.LoadFrom(path)
                    : null;
            };

    try
    {
        // hook up asm resolve handler  
        AppDomain.CurrentDomain.AssemblyResolve += tempResolveEventHandler;

        System.Configuration.Configuration config = ConfigurationManager.OpenExeConfiguration(exePath);
        Configuration.MyApp section = (Configuration.MyApp) config.Sections["MyApp"];

        if (section != null)
        {
            // "ApplicationSettings.DefaultDatabasePath" is the custom config value I'm updating
            section.ApplicationSettings.DefaultDatabasePath = Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData);
            config.Save();
        }
    }
    finally
    {
        // remove asm resolve handler.  
        AppDomain.CurrentDomain.AssemblyResolve -= tempResolveEventHandler;
    }

}