How to apply config transformations to an external config file

Question

I can't find an example of my question on the web and was wondering if anybody knew a solution. Basically, if on our web.config we point to another file, like so:

<configuration>   <configSections />   <appSettings file="AppSettings.config"> </configuration> 

then how do we apply transformations to that external file?

Basically, I want to create an AppSettings.config, AppSettings.Debug.config, AppSettings.Release.config and have a transformation run over it... Is this even possible?

Thanks in advance,

Sergio

Answer 1

There are few workarounds:

Workaround 1

• Write AppSettings.Debug.config, AppSettings.Release.config with full values (not with transform attributes)
• In your web.config, using transformation, substitute with the appropriate file:

web.debug.config

<appSettings file="AppSettings.debug.config"               xdt:Transform="SetAttributes" xdt:Locator="Match(file)"/> 

web.release.config

<appSettings file="AppSettings.release.config"               xdt:Transform="SetAttributes" xdt:Locator="Match(file)"/> 

Its less than ideal, kinda defeats the purpose of transforms but may be appropriate based on one's situation than using something like SlowCheetah.

Workaround 2

Use TransformXml build task to transform your files during build as pointed here and here

Answer 2

There's a Visual Studio plugin project called Slow Cheetah that takes the idea of transformations and allows you to apply it to files other than web.config, I haven't used it but I think it'll do what you want to do. Scott Hanselman did a blog on it.