web.config File Section Replacements - msbuild

Question

I have a web deployment project that does a web.config section replacement using an external file. (this is to change the connection strings section).
The web.config section replacement works fine when built manually, but when built as part of a TFS build the section is not replaced. I cannot find any errors or warnings in the build log.
What are the likely causes, or how can I 'debug' this?

Answer 1

Have you considered using Web.Config's ability to pull a section from a separate file? You refer to the external file like so (this is my code for loading a file that has my connection strings section):
<connectionStrings configSource="WebCS.config"/>
Then the connection string can be deployed as a separate file:
<connectionStrings>
<add name="ConnString" connectionString="Data Source=<server>;Initial Catalog=<DB>;User ID=<ID>;Password=<pwd>" providerName="System.Data.SqlClient"/>
</connectionStrings>
That way, you don't have to worry about changing the web.config file at all.

Answer 2

I am not sure this will help at all....but this is a way to add/update a connection string without having to replace the whole config section.
public static void SaveConfigVal(string connectionString, string connName)
{
System.Configuration.ExeConfigurationFileMap fileMap = new System.Configuration.ExeConfigurationFileMap();
fileMap.ExeConfigFilename = GetConfigFileName();
//System.Configuration.Configuration config = System.Configuration.ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
System.Configuration.Configuration config = System.Configuration.ConfigurationManager.OpenMappedExeConfiguration(fileMap, ConfigurationUserLevel.None);
// Retrieve the section group
ConnectionStringSettings keyValue = config.ConnectionStrings.ConnectionStrings[connName];
// If the key already exists, just replace
if (keyValue != null)
{
keyValue.ConnectionString = connectionString;
}
else
{
// Add a new key if the setting doesn't exist
config.ConnectionStrings.ConnectionStrings.Add(new ConnectionStringSettings(connName, connectionString));
}
config.Save(ConfigurationSaveMode.Modified);// (ConfigurationSaveMode.Modified);
ConfigurationManager.RefreshSection("ConnectionStrings");
}
private static string GetConfigFileName()
{
//return config file name....
}

Answer 3

If you're using or can upgrade to Visual Studio 2010, you can utilize the new web.config transformations to alter the web.config based on selected configuration.
http://msdn.microsoft.com/en-us/library/dd465318.aspx