Can web.config transforms be chained?

Let's pretend that we have the following servers [dev, test, production] and that dev and test are very similar in configuration while production is quite different.

If I'm using web.config transforms that means I have to duplicate a lot of settings för Web.dev.config and Web.test.config. It would be very nice if I could use the same transform mechanism for my transforms so that test.config is based on dev.config.

I have thought of two possible approaches, i'm not sure any of them would work:

• Try to get开发者_JAVA技巧 MSBuild to first transform dev.config and then run test.config against the result when we are running under test configuration
• trying to get the transform mechanism to work for transformations files. I would somehow run test.config against dev.config and create a temporary file which I then use as as a transformation against Web.config.

Does anyone know if something like this is possible? And if so how would one go about to set it up?

The TransformXml is just an MSBUILD task that is invoked post compile. If you extend/mod your build you can have it run the transform task twice, or allow the normal run against your configurations, then provide a second file and use the task to perform that.

If you are familiar with msbuild, this is pretty simple. If not, reply/comment, and I'll try to provide examples later today.

But in the end, yes its possible, as I've had similar need on past projects.

I have even more configurations. And all of them synced with T4. See my answer here.

Although this has been answered I wanted to update it with an answer reflecting changes made in Visual Studio 2012 that make this considerably easier.

As of Visual Studio 2012 it is possible to "chain" build and publish profile transforms.

As such you can have a "Release" build transform that takes care of common configuration such as switching off debugging, switching on custom errors, and any number of "Publish" transforms which are associated with a publish profile, adding instance specific data such as connection strings and appSettings.

In VS 2012 (as well as the publishing updates for VS2010 through the Azure SDK) now support the concept of publish specific transforms. You can also now specify the project configuration used for a profile when publishing on the publish dialog...

In this case I have created a profile named Production and set the Configuration to Release. When I publish this project the following transformations will be applied (if the files exist) in this order.

1.web.release.config

2.web.production.config

See Profile specific web.config transforms and transform preview for more information.