I have this web.config file with the compilation option set as below
Web.config
<configuration>
...
<system.web>
<compilation debug="true" targetFramework="4.5" />
...
</system.web>
</configuration>
And here is what Visual Studio puts for release mode by default.
Web.Release.config
<configuration xmlns:xdt="http://schemas.microsoft.com/XML-Document-Transform">
<system.web>
<compilation xdt:Transform="RemoveAttributes(debug)" />
</system.web>
</configuration>
I am using this for MVC4 project. Based on this tutorial, I was expecting that minified versions of js and css would be served, when the application is run under Release Mode. But this doesn't seem to be working and non-minified versions of js and css are being served. On the other hand, if I explicitly set debug to false in web.config, then the min versions are served correctly.
It seems like compilation tag Transform issue when the application is run under Release Mode, but I don't understand what's wrong with the same in Web.Release.config.
In short, I am unable to get bundling and minification working, by running application under Release Mode.
Web.config transformations as they are defined in the Web.Release.config are only done when deploying/publishing the project for the relevant configuration.
Just changing the active configuration in Visual Studio to Release and running the application does not run the transformations. Therefore, the web.config remains unchanged. This behavior is reasonable by the way as a web application is run from the project directory that contains the original web.config. If Visual Studio were to transform the web.consign, your original web.config would be changed.
If you haven't created a deployment profile yet, you can publish your application to the file system to verify the behavior. Choose Release as the configuration to run the deployment for. The transformations should be executed as expected.