Hi pkellner,
Based on my experience, I think we can do that by following steps:
1. Create a class library project
2. Add the existing files into the project
3. Change the files? property Build Action to None. (Right click the file in Solution Explorer than select Properties)
4. Configure the BAT file as the ?Post-build event command line?. (Right click the project and select Properties, go to Build Events tab and input executing BAT file string under Post-build event command Line, for example: d:\project1\test.bat)
Sincerely,
Benson Yu
Microsoft Online Community Support
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