使用Microsoft Visual Studio安装程序项目构建MSI时如何扩展user.config设置

Question

As the title suggests, I'm attempting to extend my user.config XML file that is being created in my main project to my adjacent setup project. I'm building an MSI using Microsoft Visual Studio 2017 Installer Projects (link) and also using Visual Studio 2017 to create a simple form application.

As an example, here are my two projects-

Within my main Windows Form project, I have a bool property called testBool that is set to false by default.

From my form I have a button that runs the following simple code and sets the value of testBool to true-

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Configuration;

namespace TestUserConfig
{

public partial class Form1 : Form
    {
    public Form1()
    {
        InitializeComponent();
    }

    private void button1_Click(object sender, EventArgs e)
    {
        MessageBox.Show("testBool = " + Properties.Settings.Default.testBool.ToString());

        //setting the property to true
        Properties.Settings.Default.testBool = true;

        MessageBox.Show("Test Bool = " + Properties.Settings.Default.testBool.ToString());

        //save the 
        Properties.Settings.Default.Save();

        //location of the user.config file (reference to System.Configuration required)
        Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.PerUserRoamingAndLocal);
        MessageBox.Show(config.FilePath);
    }
    }
}

This all works as expected and outputs the user.config file to the following path- C:\\Users\\USERNAME\\AppData\\Local\\Microsoft_Corporation\\PROJECTNAME_umi0kjiiephephcroktxjbzai0nh\\14.0.7208.5000\\user.config

The issue I'm having is when I build my MSI the same code does not run as I would expect. In fact the MessageBox.Show's do not even run with the exception of the last line of code – “MessageBox.Show("Hello!!”);”

I would expect the remaining message boxes to at least output a blank messagebox window.

Also, in the MSI build directory (c:\\ Program Files (x86)\\install dir) I see a file with the name “PROJECTNAME.dll.config” that contain the default value for testBool.
If I publish a click-once application the application works fine. Is there something I need to add to my setup project to make this work?

I've read every post I can find on the matter and can't seem to locate a suitable answer. I don't really want to invest tons of time into learning WIX although I might need to if that's the only route to take.

Answer 1

There a couple of issues with this approach:

1. Managed code custom actions are not instantiated the same as when run as an application. There is no native Windows Installer support for managed code, so Visual Studio setups include a C++ Dll as a shim between the running installer and your managed code. This shim loads and instantiates your managed code with reflection, bypassing the config settings stuff. This means you need to use Xml parsing to access the file.

2. Despite the fact that Visual Studio lets you do it, you should not be showing UI in the setup out of a Visual Studio custom action. It breaks silent install, group policy deployment, and the Windows Installer architecture isn't prepared to deal with UI in that stage of the install. The specific message problem is that the apartment threading doesn't have a proper UI thread. So your messageboxes won't work properly. It's not obvious from your code what you are trying to do (because it looks like a test that just sets the value and stores it) but if you had a Windows form with buttons and so on, they wouldn't work either.

If you want to get a value from a UI during the install, then use one of the additional UI forms (such as TextBoxes) and get the value from there. Then the property (default name such as EDITA1) can be passed in CustomActionData into a custom action that sets the value in the file using Xml classes. On the other hand, if this is the kind of setting used by the running app, then it's typically more appropriate to have the app do it at first run.

Another potential issue is access: files in Program Files cannot be created or updated by limited users, so trying to update settings files there can be an issue. So I would not store settings in Program Files unless they are read only. If that's an issue, just have any Xml config files in (say) User's Application Data folder (that's the location in the Visual Studio setup project's file system view).