Suppose you want to be able to run a command line tool to make changes to the transformed web.config during the publish / deploy of a web project in visual studio.

You need to be able to trigger your command after the web.config is transformed but before it is deployed. Additionally, you need to know the folder used for packaging the deploy.

Here is how.

Right click your project and unload it. Now you can right-click and select Edit the .csproj.

Down near the bottom of the csproj, you can add the following

  <Target Name="MyPublishTask" BeforeTargets="MSDeployPublish">
    <Exec Command="$(ProjectDir)..\ToolFolder\Tool.exe $(ProjectDir)$(IntermediateOutputPath)Package\PackageTmp\ web.config" />
  </Target>

Do not simply name your target “MSDeployPublish” – this overrides the publish functionality. If you use AfterTargets it will run your tool after the deploy finishes. Using BeforeTargets is just about right – it will transform the web.config and copy all the output files to the Package Temp folder. The other piece you need is the path where the package is built – $(ProjectDir)$(IntermediateOutputPath)Package\PackageTmp\ will get you there. Your tool can wreak whatever havoc necessary on the files before they are published.

One you are done editing, reload your project. Now when you publish your tool will run.