Change connection string in Windows Forms based on build configuration? - visual-studio-2010

Question

Similar to how you can have multiple Web.config's in ASP.NET, is it possible to have multiple App.config's depending on the build configuration?
I want to change my connection string, so if I am building configuration test, the connection string should be:
"Server=test;Initial Catalog=test..."
If I am building against test2, the connection string would be:
"Server=anotherserver; Initial Catalog=test2..."
Currently, I am doing it manually, so I would like to know how can I automate this?

Answer 1

Although they are not natively support, you can have XML transformations also for Windows Forms projects (App.config) and not just for Web Application projects.
There is a VS addin that enables that support and although I never tried it, it would be what I would recommend for environments where you have VS installed since is authored by at least one Microsoft employee that I'm sure has deep knowledge on MSBuild, since he already authored a book on the subject.
SlowCheetah - XML Transforms
I don't know if SlowCheetah provides support for CI servers without VS installed so I'll also throw another solution based on inclusion of custom target files.
Visual Studio App.config XML Transformation
(shameless plug notice, I was the original author of the one above)

Answer 2

We use a strategy here that seems to work well. We have one Web.config per solution. I assume this will work with app.configs also, but have never tried it. You create a class, call it e.g., ConfigurationManager. In the class should go this code:
public static class ConfigurationManager
{
private static NameValueCollection _appSettings = new NameValueCollection();
private static ConnectionStringSettingsCollection _connSettings = new ConnectionStringSettingsCollection();
private enum SettingsType {App, Connection};
public static NameValueCollection AppSettings
{
get
{
if (_appSettings.Count == 0)
{
LoadEnvironmentSettings(SettingsType.App);
}
return _appSettings;
}
}
public static ConnectionStringSettingsCollection ConnectionStrings
{
get
{
if (_connSettings.Count == 0)
{
LoadEnvironmentSettings(SettingsType.Connection);
}
return _connSettings;
}
}
private static void LoadEnvironmentSettings(SettingsType settingsType)
{
string strEnvironment = string.Empty, strSeparator = ".";
if (ConfigurationManager.AppSettings.HasKeys())
{
strEnvironment = ConfigurationManager.AppSettings["Environment"];
if (!String.IsNullOrEmpty(strEnvironment))
{
strEnvironment += strSeparator;
switch (settingsType)
{
case SettingsType.App:
LoadAppSettings(strEnvironment.ToUpper());
break;
case SettingsType.Connection:
LoadConnectionSettings(strEnvironment.ToUpper());
break;
}
}
else //that part should never happen
{
throw new Exception("Missing Environment AppSetting");
}
}
}
private static void LoadAppSettings(string environmentType)
{
string appKey = string.Empty;
foreach (string key in ConfigurationManager.AppSettings.AllKeys)
{
if (key.StartsWith(environmentType))
{
appKey = key.Replace(environmentType, string.Empty);
_appSettings.Add(appKey, ConfigurationManager.AppSettings[key]);
}
}
}
private static void LoadConnectionSettings(string environmentType)
{
//ConnectionStringSettings connStrings = new ConnectionStringSettings();
string connKey = string.Empty;
foreach (ConnectionStringSettings str in ConfigurationManager.ConnectionStrings)
{
if (str.Name.StartsWith(environmentType))
{
connKey = str.Name.Replace(environmentType, string.Empty);
_connSettings.Add(new ConnectionStringSettings(connKey, str.ConnectionString));
}
}
}
}
You need to add System, System.Collections.Generic, System.Collections.Specialized, System.Configuration and System.Text. Make sure your class is in the same namespace as the project you're working on. Then, in your config file you add two (or more) keys, e.g.,
<add name="TEST.MyConnectionString" connectionString="Data Source=TESTServer;Initial Catalog=MyDatabase;user id=MyUser;pwd=Mypwd" />
<add name="TEST2.MyConnectionString" connectionString="Data Source=TEST2Server;Initial Catalog=MyDatabase;user id=MyUser;pwd=Mypwd" />
Finally, in your machine.config, you add the following in appSettings:
<add key="Environment" value="TEST"/>
or
<add key="Environment" value="TEST2"/>
Depending on what you want to do. We usually put DEV, STAGING and PROD keys and then have different machine.config files on our three different DEV, STAGING and PROD servers. Hope this helps