We Keep Coding

Use App.config with a Custom Section shared between two different projects

Scenario
I have developed a windows service which is configured by its App.config file.
This file contains the information in the standard sections (connectionStrings, appSettings) and in a custom section (sourceTabSection).
In the windows service project i have 4 classes which allow me to get/set the config file content. They are based on what is written in this article: Writing a Custom ConfigurationSection to handle a Collection and i have no problems on using them inside my service.
The problems come when i try to get/set the custom section (with the standard sections i don't have any problems) of the App.config, belong to the Windows service, using another application that in my case is a Windows Form that allows users to view/set parameters for the windows service.
The Windows Form application has the same pack of 4 classes used by the service, in order to handle the App.config.
When the code that get/set custom parameters of Windows Service is excuted on the Windows Form app I get the following error message:
{"An error occurred creating the configuration section handler for sourceTabSection: Could not load type 'DataReportingService.CustomSourceTabSection.SourceTabSection' from assembly 'DataReportingService'."}
The problem is due to this following line of code in the App.config
<section name="sourceTabSection" type="DataReportingService.CustomSourceTabSection.SourceTabSection, DataReportingService"/>
The attribute type of the tag shown above has the following meaning (it's explained here: section Element for configSections):
type="Fully qualified class name, assembly file name, version, culture, public key token"
Following what is written on Writing a Custom ConfigurationSection to handle a Collection article I defined only the first two parameter (Fully qualified class name, assembly file name) of the attribute type. Microsoft documentation (no more maintained) doesn't specify that the other parameters can be not defined, but the example that I followed and others use this approach.
However the point is this phrase about the type attribute on Microsoft documentation:
The assembly file must be located in the same application directory
So, due to this bond, seems to be impossible to handle custom section of an application A from another application B (which has another assembly) using this approach.
So do you know how could I solve this problem?
Windows service - App.config
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<configSections>
<section name="sourceTabSection" type="DataReportingService.CustomSourceTabSection.SourceTabSection, DataReportingService"/>
</configSections>
<!-- *** CUSTOM SECTION *** -->
<sourceTabSection>
<Tables>
<sourceTab name="TEST" db_conn_str="****"
keep_time="1" scan_frequency_process_rows="1"
scan_frequency_delete_processed_rows="1" />
<sourceTab name="TEST_2" db_conn_str="****"
keep_time="1" scan_frequency_process_rows="1"
scan_frequency_delete_processed_rows="1" />
</Tables>
</sourceTabSection>
<!-- *** STANDARD SECTIONS *** -->
<connectionStrings>
<add name="DB_Target" connectionString="Data Source=192.168.2.2;Initial Catalog=PlantDompe;Persist Security Info=True;User ID=sa;Password=Gf6swML0MXiqbOFuvRDvdg==;"
providerName="System.Data.SqlClient" />
</connectionStrings>
<appSettings>
<add key="TAB_ALARMS_TARGET" value="AlarmsProcess" />
<add key="TAB_VALUE_TARGET" value="USER_CHANGES" />
<add key="TAB_LOGINS_TARGET" value="USER_LOGONS" />
<add key="LOG_DIR" value="C:/Users/rossi/Documents/Visual Studio 2017/Projects/DRS_proj/Log/" />
</appSettings>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.2" />
</startup>
<system.web>
<trust level="Full" />
<webControls clientScriptsLocation="/aspnet_client/{0}/{1}/" />
</system.web>
</configuration>
Ugly solution
If found a work around to this problem by performing the two following steps on the Windows Form application that need to view/set the parameters (custom and no custom) inside the App.config of the Windows Service:
Using visual studio i go to Solution Properties > Application tab, and I change the following values
Assembly name = DataReportingService
Default namespace = DataReportingService
Note: DataReportingService is the name of the window service with the App.config file
Find and replace all the references to old namespace with the new one
In this way I can handle the custom section of the App.config, but honestly it's a really ugly solution and I think that there should be something better.

Thanks #Alex Paven, your comment has helped me to solve this problem!
Here below there are the detailed steps of what I've done:
I moved the 4 classes which handles the Windows service config file in a Class Library project (.NET Framework) called: DRS_CustomConfig.
I changed the namespace of the 4 classes with the following value: DRS_CustomConfig and then I compiled the project.
I linked the external library both in the Windows service project and in Windows Form application
For each class of both projects which need to use the classes contained in the external library I inserted the following piece of code:
using DRS_CustomConfig;
In the App.config of the Windows service I changed the section element as follows:
Old
<section name="sourceTabSection"
type="DataReportingService.CustomSourceTabSection.SourceTabSection,
DataReportingService"/>
New
<section name="sourceTabSection"
type="DRS_CustomConfig.SourceTabSection, DRS_CustomConfig"/>

Web.config Configsource and file attributes not applied when unit testing

I have a Appsettings type initializer in my main project, which gets strings from appSettings in my web.config file. This appSettings section and my connectionStrings section use attributes like configSource, file to reference values.
It all works, except for when my unit testing project tries to test it.
An error is thrown in the type appSettings type initializer, that the appSettings/connectionStrings values in web.config aren't defined.
How can I get my Applicaton to intiailize properly so the web.config is accessible?
Do I need to initialize an instance my main project ( the MVCApplication )?
It's causing Entity framework to have no connection string also, cause value not set in web.config

I suggest adding an App.config to your Unit test project and reference your /Configs/AppSettings.local.config within your app.config.
<configuration>
<appSettings file='/Configs/AppSettings.local.config' />
</configuration>

AppSettings in App or Web Config Using a Linked File

I'm trying to reference some common config settings between a Windows Service and an ASP.NET MVC website. I am doing this by using the file attribute on appSettings in either the App.config or Web.config (respectively). The file (named common.config) that is being referenced is a linked file in a separate project in the same solution. That common.config is set to Content with Copy Always in both projects.
This stack answer to a similiar question seems to suggest at least for configSource this solution would work. I don't want configSource though as I only want a handful of the properties to be common amongst the two projects. Update: I just tried this, and the configSource also doesn't work. It can't find the config file. This leads me to believe the common.config is not treated as content with copy always.
Example App.config
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<appSettings file="common.config">
<add key="NotCommonKey" value="1"/>
</appSettings>
</configuration>
Example Web.config
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<appSettings file="common.config">
<add key="NotCommonKey2" value="2" />
</appSettings>
</configuration>
Example common.config (Content -> Copy Always)
<appSettings>
<add key="CommonKey" value="1" />
</appSettings>
I am using ConfigurationManager / WebConfigurationManager reading from the AppSettings property.
Any ideas why when the common.config is a linked file, it's AppSettings values are not used and when it is not linked it works as normal?
Thanks!

In the Web.Config you must add "bin/" (se example below).
By default the web.config is NOT copied into the bin folder but the file common.config is, therefore you must add the path from web.config. In a non-web project the default behavior is that the App.config is copied to the bin folder with name MyProgram.exe.config and is in the same directory as common.config.
<appSettings file="bin/common.config">

The idea of using "bin/..." is good but leads to an error saying that "/" is an invalid character in the resulting virtual path.
The proper solution is tu use "bin...".
Cheers

I use this to access another .exe's config file, not sure whether it will work with a MVC project, but this might get you closer:
string proj2Exe = #"C:\projects\proj2\bin\Debug\proj2.exe";
Configuration proj2Config = ConfigurationManager.OpenExeConfiguration(proj2Exe);
string mysetting = proj2Config .AppSettings.Settings["ThatSetting"].Value;

Hiding private details from open source projects

I have a .net github project that is basically a wrapper around a web API. In the test project, I am calling to the API using an API key. I need to keep this key private, how do I accomplish this in a visual studio project?
In some other projects, like python, I can have git ignore the file (config.py) and use something like config.example.py. But in visual studio's case, the project will not compile because of the missing file Config.cs. What is the proper way to solve this? I'm thinking of using this same method of ignoring the file and have them execute a build script that should rename Config.example.cs to Config.cs?

This is the perfect for .config files. Depending on whether its a web or console application, you will have a web.config or app.config file in your project.
You can use the appSettings section to store your API key.
To make things even easier, you can actually have this section read from another file, ie: specialappsettings.config and then just ignore that single file from your repository.
Modify your web.config (or app.config):
<configuration>
<appSettings file="specialappsettings.config">
</appSettings>
<system.web>
<!-- standard web settings go here -->
</system.web>
</configuration>
Create a new specialappsettings.config file:
<appSettings>
<add key="APIKey" value="YourApiKeyValue" />
<add key="AnotherKey" value="AnotherValue" />
</appSettings>
This can be accessed in your code via:
var apiKey = ConfigurationManager.AppSettings["APIKey"];
Notes:
You can keep your settings within the original web.config file as
well but this lets you ignore just the specific settings file from
your git repository without affecting the rest of the project's
necessary configuration details.
The same "key" can be saved in
either file however the external file will override the original
web.config file value.

You are probably looking for the App.config file for a project. It will be copied to <application>.exe.config when you compile it. Users can edit that config file as needed.
In that config file, you can add your API keys:
<configuration>
<appSettings>
<add key="APIKey" value="12345"/>
</appSettings>
</configuration>
Then you can access it from your code using ConfigurationManager.AppSettings:
string apiKey = ConfigurationManager.AppSettings["APIKey"];

One option is to use .config files instead of having secret keys hardcoded in sources.
More info Using Settings in C# and step-by-step guide
<configuration>
<appSettings>
<add key="SecretKey" value="0" />
</appSettings>
</configuration>
var secretKey = ConfigurationManager.AppSettings.Get("SecretKey");

Perhaps you can store the key outside of the Config.cs file and load it at run time.
Bonus, other people using your code won't have to recompile the project to change to their API key.

C# - Use configuration file in Debug mode

I discovered few days ago that we can use Configuration files in .NET and trying to use it in my applications.
First of all, configure correctly the use of configuration file is really borring :
Configuration file should have the same name as the application (understandable)
Then think to add the System.Configuration reference (understandable too)
When file is added, go in it's properties and change it to copy the file in output directory (less understandable).
Configuration file isn't taken into account in debug mode (because of *.vhosts.exe)
It takes me time to understand why this file wasn't taken into account...
So question is pretty simple, how can I fix this and use configuration files in Debug Mode ?
I would use it in order to configure my trace switches.
Here is my App.config file :
<configuration>
<appSettings>
<add key="A" value="B"/>
</appSettings>
<system.diagnostics>
<switches>
<add name="myFirstSwitch" value="1" />
<add name="MySecondSwitch" value="Error" />
</switches>
</system.diagnostics>
</configuration>
Thanks.

I think you created your config file the wrong way, the right way is:
On the Project menu, click Add New Item. The Add New Item dialog box
appears.
Select the Application Configuration
File template and then click Add. A
file named App.config is added
to your project.
This config file is automatically copied to the build folder when you build the project and works in both Debug and Release mode.