Configure App.config Application Settings During MSI Install vb.net - vb.net

Question

I am trying to create an msi install for my windows service. The reason for creating an msi is that the intended users want to be able to quickly install the service with as-little intervention as possible.
i can get the service to install as a msi but i have a variable within my code that i need the user to define when the msi is being installed. the variable i require from the user is the file path which they want the xml files my service creates to be located.
i thought i could configure the app.config application settings to contain the file path that the xml files should be written to. However i'm struggling to do this and im not to sure if its the best way to do it?
I have my setup project that contains my executable and has my textbox which will contain the one variable from the user.
I have an installer class which contains my serviceinstaller and process installer. This is where im struggling to understand what i need to do next.
Do i need to override the install method? The current code of my installer class was automatically generated and is as follows:
Imports System.Configuration.Install
Imports System.Configuration
<System.ComponentModel.RunInstaller(True)> Partial Class ProjectInstaller
Inherits System.Configuration.Install.Installer
'Installer overrides dispose to clean up the component list.
<System.Diagnostics.DebuggerNonUserCode()> _
Protected Overrides Sub Dispose(ByVal disposing As Boolean)
Try
If disposing AndAlso components IsNot Nothing Then
components.Dispose()
End If
Finally
MyBase.Dispose(disposing)
End Try
End Sub
'Required by the Component Designer
Private components As System.ComponentModel.IContainer
'NOTE: The following procedure is required by the Component Designer
'It can be modified using the Component Designer.
'Do not modify it using the code editor.
<System.Diagnostics.DebuggerStepThrough()> _
Private Sub InitializeComponent()
Me.ServiceProcessInstaller1 = New System.ServiceProcess.ServiceProcessInstaller()
Me.ServiceInstaller1 = New System.ServiceProcess.ServiceInstaller()
'
'ServiceProcessInstaller1
'
Me.ServiceProcessInstaller1.Account = System.ServiceProcess.ServiceAccount.LocalSystem
Me.ServiceProcessInstaller1.Password = Nothing
Me.ServiceProcessInstaller1.Username = Nothing
'
'ServiceInstaller1
'
Me.ServiceInstaller1.ServiceName = "Spotter"
Me.ServiceInstaller1.StartType = System.ServiceProcess.ServiceStartMode.Automatic
'
'ProjectInstaller
'
Me.Installers.AddRange(New System.Configuration.Install.Installer() {Me.ServiceProcessInstaller1, Me.ServiceInstaller1})
End Sub
Friend WithEvents ServiceProcessInstaller1 As System.ServiceProcess.ServiceProcessInstaller
Friend WithEvents ServiceInstaller1 As System.ServiceProcess.ServiceInstaller
End Class
I can even add the CustomActionData values. The string determines what gets passed into the context object that i used to collect the user value that is entered. param1 being my variable name.
I'm pretty much struggling with the installer code...i think?

Answer 1

One option to consider is using a third party installer, such as Installshield, that has builtin support for modification of xml configuration files, such as config files.
However, if you want to roll your own, you definitely need to override the Install method. Any parameters that you pass in CustomData will be available in the dictionary that is passed as a parameter to this method.
For example:
Public Overrides Sub Install(ByVal stateSaver As System.Collections.IDictionary)
MyBase.Install(stateSaver)
If Me.Context.Parameters.Count <> 0 Then
For Each sKey As String In Context.Parameters.Keys
Select Case sKey.ToUpper
Case "PARAM1"
' XML directory
Me.XMLDir = Context.Parameters(sKey)
End Select
Next
End If
End Sub
In cases like this, we always write the value to the registry so that the user doesn't have to re-enter it if they uninstall or reinstall.
I am not sure of the exact sequence of events for modifying the app.config, but you could write to the registry, then modify app.config when the service is first started.
You will probably also find that you need to remove the custom action from the Commit phase in order for your installer to work successfully.