How to version DLLs using TeamCity
It’s useful to include a version in DLLs that you deploy, to make it easy to check what code is actually being used where. We build our projects using TeamCity, and it’s possible to write build scripts that grab the version from an environment variable that TeamCity sets in order to insert into your AssemblyInfo.cs files. However, if you have a fairly standard project setup and are using TeamCity, there’s an easier way to do this using the AssemblyInfo Patcher build feature that TeamCity provides. This will run after all files have been checked out, automatically searching for all AssemblyInfo.cs files and replacing relevant versions (e.g. in the [assembly: AssemblyVersion("1.0.0.0")] attribute) with the current build number, before then proceeding as normal with the build, and reverting the changes once the build has finished.
To enable this feature, simply edit the configuration settings for the build you wish to add it to, click “Build Features” in the sidebar on the left, then click the “Add build feature” button and select “AssemblyInfo patcher” from the options. Configuration is fairly minimal but will allow you to customise the format of the version that will be used for various different attributes, if you don’t want to just use the default build version.
The AssemblyInfo Patcher is just a pre-configured version of the TeamCity File Content Replacer build feature, which you can use if you have more advanced needs.
