multiple applications single config file - service

Question

I'm trying to write a service and configuration application. VB/C++ 2010 I've had a number of hits on google but they largely seem to be obsolete. What I have so far is a project with a single form app and a service app. The single form app has an "app.config" file and I have added a section:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<appSettings file="settings.config">
</appSettings>
</configuration>
In the Solution I have added a "settings.config" file and its contents is:
<?xml version="1.0" encoding="utf-8"?>
<appSettings>
<add key="Setting1" value="This is Setting 1 from settings.config" />
<add key="Setting2" value="This is Setting 2 from settings.config" />
<add key="ConnectionString" value="ConnectString from settings.confg" />
</appSettings>
I have added a reference to then C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework\v4.0\Profile\Client\System.Configuration.dll
library in both the forms app and the service app
In the very simple forms app i have the following code
Private Sub Form1_Load(sender As Object, e As System.EventArgs) Handles Me.Load
Dim s As String = _
System.Configuration.ConfigurationManager.AppSettings("ConnectionString")
TextBox1.Text = s
End Sub
It doesn't work! Now clearly I am missing something. Its probably very simple. But my limited understanding is that this is automatically configuered by the config files I have? MS in their usual helful fashion seem to only give samples for 2012 and net 4.5 or greater. I need this to work on a 2003 server (as well) so I'm limited to net 4.0

Answer 1

The problem here is that the line System.Configuration.ConfigurationManager.AppSettings("ConnectionString") is looking for the key ConnectionString in your application's app.config file.
The fact that you have included that file key in your app.config file doesn't magically tell the ConfigurationManager to load the settings from a different file. If that's what you want you will have to read the setting for the file key and then manually load the configuration from that file.
This has not changed since the early versions of .Net though so I'm not sure why you were conflicted by the examples.

Answer 2

Add reference on existing assembly in .Net section of your Add Reference Popup
But i suggest you to use connectionStrings section in your config file
<connectionStrings>
<add name="myConnectionString" connectionString="server=localhost;database=myDb;uid=myUser;password=myPass;" />
</connectionStrings>
string connStr = ConfigurationManager.ConnectionStrings["myConnectionString"].ConnectionString;