Override ConnectionStrings in app.config (or web.config)

Question

Is there a way to override a ConnectionString in an app.config. Our buildsystem runs also on a server of a customer, but there the connectionString needs to be different. Because the app.config is in svn, everytime I change something in the app.config and commit it, I need to go to the server of the customer to change the connectionString back to their database...

In ant-scripts for example, this is no problem, but in an app.config I can't seem to find a way. Tried this for example:

<connectionStrings configSource="WebConnectionString.config">
  <add name="ConnectionString"
    connectionString="..." 
    providerName="System.Data.SqlClient"/>
</connectionStrings>

What I'm trying to do is that if WebConnectionString.config exists, then use the connectionString in that config file. If it doesn't, use the one defined in code sample (so, in app.config).

Answer 1

WEB DELPOYMENT PROJECTS WOOHOO

What a way to save yourself loads of deployment grief. The one amazingly wonderful beautiful thing you can do is have a Build configuration for each customer.

Then you can also have a config file for each customer which contains the connections strings. Depending on which build configuration you choose the different connectionstrings will be pasted into the web.config. So now you can build a 'different' site for each customer it's soo easy.

Imagine a folder called config and files like cust1ConnectionString.cfg, cust2... etc

Now you create configurations. You are already familiar with Release and Debug, create cust1, cust2.

Then in the web deployment project there is an option to replace secions of the web config with sections from another file.

So you go to cust1 deployment and tell it that the connection string are in the file cust1connectionstrings.cfg. Tell it where cust2 is etc....

And now no more pissing around, everytime you build the site for a customer all there settings are inserted into the web.config and you can just hand over a correctly configured site. It doesn't matter what's in SVN cause each customer has there own config. Sweet

Answer 2

You could do this using the configSource attribute, but you would have to have one for each platform/environment, because the element has to be empty when using this feature:

However, when you use the configSource attribute, you must move the entire section to the separate file because there is no merging of element settings.

It's only the AppSettings section that allows you to override values like this with the file element.

Something to think about: VS2010 has a feature that allows you to modify the config files based on build target (live/release/debug/test etc).